BRPI0807111A2 - PNEUMATIC - Google Patents

Description

PNEUMATIC Technical Field

The present invention relates to a tire, and particularly to a tire including turbulence-producing bulges.

BACKGROUND ART

Generally, an increase in tire temperature of a tire is considered to be undesirable in terms of durability because such a temperature increase promotes a time-dependent change, which is a change in the physical properties of a material, or contributes to damage in a tire. tread part and similar in high speed drive. A reduction in tire temperature for improved durability is now an important task to be performed especially for heavy duty tires, including off-road radial tires (ORR), truck and bus radial tires (TBR), and rolling tires. voids being fired while drilled (fired under an internal pressure of OkPa).

For example, when a flat tire with crescent-shaped side reinforcement layers is fired while punctured, deformation in the radial direction of the tire concentrates on the side reinforcement layers. Consequently, the temperature in the side reinforcement layers rises so much as to considerably affect durability.

A technique has been disclosed for reducing the tire temperature in such a tire (Japanese Patent Application Publication No. 2006-76431). In the art, a reinforcement element is provided to reduce or suppress deformation of tire components (such as, in particular, a carcass layer in a portion located in a side portion and a bead portion).

However, the conventional tire described above has a problem of degrading general steering performance, such as handling stability and ride comfort. This is because the provision of the reinforcement element leads to an increase in tire weight and a new unintended breakage occurrence as separation in the reinforcement element. Particularly, on a flat tire, there is a concern that the reinforcement element increases the vertical elasticity (vertical elasticity of the tire) of the driven tire at normal internal pressure, resulting in degradation in overall steering performance. Therefore a measure that does not impair the performance of general management has been sought.

The present invention has been made in consideration of such circumstances, and is intended to provide a tire capable of efficiently reducing tire temperature while maintaining general steering performance.

DISCLOSURE OF INVENTION

Based on the above circumstances, the inventors have analyzed an efficient reduction in tire temperature. As a result, it was found that the heat dissipation rate of the tire temperature was increased by increasing a fluid velocity gradient (rate) generated around a tire along with tire rotation.

The present invention therefore has the following aspects. First, a first aspect of the present invention is a tire summarized as follows. Specifically, the tire has turbulence bumps on the surface of a tire, each of the turbulence bumps having an acute edge portion. In the tire, the following ratios are satisfied: O.015 <H / VR <0.64; THE . 005 <H / VR <0.02; 1.0 <w / H <50.0; 0.1 <H / e <3.0; I.0 <L / H <50.O; and 1.0 <(p- w) /w ^ 100OO, where "R" is a tire radius being a distance from a rim center to an outermost position in a radial tread direction, "H" is a maximum protrusion height being a distance from the tire surface to a position at which each turbulent protrusion projects further from the tire surface, "p" is a circumferential protrusion direction interval being a gap between the turbulent generating protuberances adjacent in a tire rotation direction, "e" is a radial bulge direction range being a gap between the bulges that generate adjacent turbulence in an orthogonal direction of rotation substantially orthogonal to the tire rotation direction, "L" is a radial bulge direction length being a maximum length of each turbulence generating bulge in the orthogonal direction of rotation, and "A" is a length of di circumferential bump reaction with a maximum length of each turbulence generating bump in the direction of tire rotation.

Note that the tire surface includes an outer tire face (e.g., outer surfaces of a tread portion and a side portion) and an inner tire face (e.g., an inner surface of an inner liner). In addition, the settings of each bulge are all expressed in millimeters (mm).

Another aspect of the present invention is summarized in which an average arrangement density (p) of turbulence-producing bulges is from 0.0008 to 13 pieces / cm2.

Another aspect of the present invention is summarized in that the average arrangement density (p) of the turbulence-producing bulges gradually decreases from an inner side in a radial tire direction towards an outer side in a radial tire direction.

Another aspect of the present invention is summarized in that the turbulence generating bulges are arranged at predetermined intervals in respective directions: a direction in which turbulence is generated to flow in a direction opposite to the tire rotation direction; and an orthogonal direction to turbulence, and are arranged in a dispersed mode in which the adjacent turbulent generating protuberances in the turbulence generating direction are arranged at respective positions offset from each other.

Another aspect of the present invention is summarized in that a circumferential protrusion (CL ') centerline tilts relative to the tire rotation direction by 10 ° to 20 °, with a rear side thereof in the tire rotation direction being outwards, in the radial direction of the tire, from a front side of the tire in the direction of rotation of the tire, the circumferential bulge direction center line (CL ') being a line that connects centers of the respective bulges that generate adjacent turbulence in the Tire rotation direction.

Another aspect of the present invention is summarized in that, in a bulge top view being a view in which each turbulent bulge is viewed from the top, a front face of the bulging turbulence is at least partially curved, the front face being located to forward, in the direction of tire rotation, of a radial bulge (CL) direction centerline. In addition, a front angle (Θ1) and a rear angle (Θ2) are individually set to a value between 45 ° and 135 °, including the front angle (Θ1) being an angle formed between the tire surface and the front face. , the rear angle (Θ2) being an angle formed between the tire surface and a rearwardly located rear face, in the tire rotation direction, of the radial direction centerline (CL).

Another aspect of the present invention is summarized in that, in a bulge top view being a view in which each turbulent bulge is viewed from the top, a front convex portion is provided forward, in the direction of tire rotation, of the centerline. (CL) of radial bulge direction, the front convex part protruding forward in the direction of tire rotation.

Another aspect of the present invention is summarized in that, in a bulge top view being a view in which each turbulent bulge is viewed from the top, a front face located forward in the direction of tire rotation of the centerline (CL ) Radial bulge steering has a front inner point (Ql) located in an innermost position in a radial tire direction, and a front outer point (Q2) located in an outermost position in a radial tire direction, the inner point (Ql) being located forward, in the direction of tire rotation, from the front outer point (Q2).

Another aspect of the present invention is summarized in that, in a bulge top view being a view in which each turbulent bulge is viewed from the top, at least one of a rear convex portion and a rear concave portion is provided rearwardly in the tire rotation direction, from the radial bulge direction centerline (CL), the rear convex portion protruding backward in the tire rotation direction, the rear concave portion being concave forward in the tire rotation direction. Another aspect of the present invention is summarized wherein an inner angle (Θ3) and an outer angle (Θ4) are individually defined at a value between 45 ° and 135 °, inclusive, the inner angle (Θ3) being an angle formed between the surface. and an inner face located in an innermost position in a radial tire direction, the outer angle (Θ4) being an angle formed between the tire surface and an outer face located in an outermost position in the radial tire direction.

Another aspect of the present invention is summarized in that a maximum front angle (Θ5) and a maximum rear angle (Θ6) are individually set to a value between 45 ° and 135 °, inclusive, the maximum front angle (Θ5) being a formed angle. between a projecting position and a position where the tire surface intersects with a front face located forward, in the tire rotation direction, of the radial bulge centerline (CL), the most projected position projecting farthest from the tire rear surface, the maximum rear angle (Θ6) being an angle formed between the most projected position and a position where the tire surface intersects with a rear face located rearward in the direction of tire rotation of the centerline (CL) of radial bulge direction.

Another aspect of the present invention is summarized wherein an inner maximum angle (Θ7) and an outer maximum angle (Θ8) are individually defined at a value between 45 ° and 135 °, inclusive, the inner maximum angle (Θ7) being an formed angle. between a more projected position and a position where the tire surface intersects with an inner part located in an innermost position in a radial tire direction, the most projected position protruding farther from the tire surface, the maximum external angle (Θ8 ) being an angle formed between the most projected position and a position where the tire surface intersects with an outer part located in one position

outermost in radial direction of tire.

Brief Description of Drawings

Figure 1 is a partially detailed perspective view showing a tire according to a first embodiment.

Figure 2 is a cross-sectional view showing the tire according to the first embodiment taken in a tread direction.

Figure 3 is a plan view of the main part showing the protrusion arrangement state in accordance with

with the first mode (part 1).

Figure 4 is a plan view of the main part showing the arrangement state according to the first embodiment (part 2).

Figure 5 is a perspective view showing

the bulge according to the first mode (part 1) ·

Figure 6 is a perspective view showing the protuberance according to the first embodiment (part 2).

Figure 7 is a side view and a top view showing the protrusion according to the first embodiment (part 2).

Figure 8 is a side view showing the protrusion according to the first embodiment.

Figure 9 is a top view showing the proximity of the protuberance according to the first embodiment. Figure 10 is a schematic top view showing the protrusion according to the first embodiment.

Figure 11 is a perspective view showing the protuberance according to the first embodiment (part 3).

Figure 12 is a characteristic graph showing an average protrusion density of the protuberances and a degree of heat transfer coefficient improvement, which are obtained by experiments according to the first embodiment.

Figure 13 is a graph showing a heat transfer coefficient of the example tire according to the first embodiment (part 1).

Figure 14 is a graph showing a heat transfer coefficient of the tire of the examples according to the first embodiment (part 2).

Figure 15 is a graph showing a heat transfer coefficient of the tire of the examples according to the first embodiment (part 3).

Figure 16 is a graph showing a heat transfer coefficient of the tire of the examples according to the first embodiment (part 4).

Figure 17 is a graph showing a heat transfer coefficient of the tire of the examples according to the first embodiment (part 5).

Figure 18 is a graph showing a heat transfer coefficient of the tire of the examples according to the first embodiment (part 6).

Figure 19 is a perspective view showing a protrusion according to a second embodiment.

Figure 20 has top, cross-sectional and front views each showing the protrusion according to the second embodiment. Fig. 21 is a view to illustrate protrusion operations and effects according to the second embodiment.

Figure 22 is a top view showing a protrusion of Modification 1 according to the second embodiment.

Fig. 23 is a perspective view showing a protrusion of Modification 2 according to the second embodiment.

Figure 24 has top, cross-sectional and front views each showing the bulge of Modification 2 according to the second embodiment.

Figure 25 is a top view showing the protrusion of Modification 2 according to the second embodiment.

Figure 26 is a perspective view showing a protrusion of Modification 3 according to the second embodiment.

Figure 27 has top, side and front views each showing the bulge of Modification 3 according to the second embodiment.

Figure 28 has perspective and side views each showing the protrusion of the modification 3 according to the second embodiment (part 1).

Fig. 29 has perspective and side views each showing the protrusion of the modification 3 according to the second embodiment (part 2).

Figure 30 has perspective and side views each showing the protrusion of the modification 3 according to the second embodiment (part 3).

Fig. 31 is a perspective view showing a protrusion of Modification 4 according to the second embodiment. Figure 32 has top, cross-sectional and front views each showing the protrusion of Modification 4 according to the second embodiment.

Fig. 33 has perspective and front views each showing the protrusion of Modification 4 according to the second embodiment (part 1).

Figure 34 has perspective and front views each showing the protrusion of Modification 4 according to the second embodiment (part 2).

Figure 35 has perspective and front views each showing the protrusion of Modification 4 according to the second embodiment (part 2).

Figure 36 is a graph showing the tire durability of the examples according to the second embodiment (part 1).

Figure 37 is a graph showing durability of the example tires according to the second embodiment (part 2).

Fig. 38 is a perspective view showing a protrusion according to a third embodiment.

Fig. 39 has top cross-sectional and front views each showing the protrusion according to the third embodiment.

Fig. 40 is a view to illustrate protrusion operations and effects according to the third embodiment.

Fig. 41 is a top view showing a protrusion of Modification 1 according to the third embodiment.

Fig. 42 is a perspective view showing a protrusion of Modification 2 according to the third embodiment. '

Figure 43 has top, cross-sectional and front views showing each protrusion of Modification 2 according to the third embodiment.

Fig. 44 is a top view showing the protrusion of Modification 2 according to the third embodiment.

Fig. 45 is a perspective view showing a protrusion of Modification 3 according to the third embodiment.

46 is a top view showing the protrusion of Modification 3 according to the third embodiment.

Figure 47 has perspective and side views each showing the bulge of Modification 3 according to the third embodiment (part 1).

Figure 48 has perspective and side views each showing the bulge of Modification 3 according to the third embodiment (part 2).

Fig. 49 has perspective, top and side views each showing the protrusion of the modification 3 according to the third embodiment (part 3).

Fig. 50 is a perspective view showing a protrusion of Modification 4 according to the third embodiment.

Fig. 51 has top, cross-sectional and front views each showing the protrusion of Modification 4 according to the third embodiment.

Fig. 52 has perspective and front views each showing the protrusion of Modification 4 according to the third embodiment (part 1).

Fig. 53 has perspective and front views each showing the protrusion of modification 4 according to the third embodiment (part 2).

Fig. 54 has perspective, top and front views each showing the protrusion of Modification 4 according to the third embodiment (part 3).

Fig. 55 is a perspective view showing a protrusion according to a fourth embodiment.

Fig. 56 has top, cross-sectional and front views each showing the protrusion according to the fourth embodiment.

Fig. 57 is a view to illustrate protrusion operations and effects according to the fourth embodiment.

Fig. 58 is a top view showing a protrusion of Modification 1 according to the fourth embodiment.

Fig. 59 is a top view showing a protrusion of modification 2 according to the fourth embodiment.

Fig. 60 has top cross-sectional and front views each showing the bulge of modification 2 according to the fourth embodiment.

Fig. 61 is a top view showing the protrusion of Modification 2 according to the fourth embodiment.

Fig. 62 is a perspective view showing a protrusion of Modification 3 according to the fourth embodiment.

Fig. 63 has top, side and front views each showing the bulge of Modification 3 according to the fourth embodiment (part 1).

Fig. 64 has perspective and side views each showing the protrusion of Modification 3 according to the fourth embodiment (part 1).

Fig. 65 has perspective and side views each showing the bulge of Modification 3 according to the fourth embodiment (part 2).

Fig. 66 has perspective, top and side views each showing the protrusion of Modification 3 according to the fourth embodiment (part 2).

Fig. 67 is a perspective view showing a protrusion of Modification 4 according to the fourth embodiment.

Fig. 68 has top, cross-sectional and front views each showing the protrusion of Modification 4 according to the fourth embodiment (part 1).

Fig. 69 has perspective and front views each showing the protrusion of Modification 4 according to the fourth embodiment (part 1).

Fig. 70 has perspective and front views each showing the protrusion of Modification 4 according to the fourth embodiment (part 2).

Fig. 71 has perspective, top and front views each showing the protrusion of Modification 4 according to the fourth embodiment (part 2).

Fig. 72 is a partially detailed perspective view showing a tire according to a fifth embodiment (part 1).

Fig. 73 is a partially detailed perspective view showing the tire according to the fifth embodiment (part 2).

Figure 74 is a partially detailed perspective view showing the tire according to the fifth embodiment (part 3).

Fig. 75 is a partially enlarged perspective view showing a tread portion and a cross-sectional view showing the vicinity of a notch of a tire according to a sixth embodiment (part 1). Fig. 76 is a partially enlarged perspective view showing the tread portion and a cross-sectional view showing the proximity of the notch of the tire according to the sixth embodiment (part 2).

Figure 77 is a partially enlarged perspective view showing the tread portion and a cross-sectional view showing the proximal notch of the tire according to the sixth embodiment (part 3).

Fig. 78 is a partially enlarged perspective view showing the tread portion and a cross-sectional view showing the proximity of the notch of the tire according to the sixth embodiment (part 4).

79 is a partially enlarged perspective view showing the tread portion and a cross-sectional view showing the proximal notch of the tire according to the sixth embodiment (part 5).

Fig. 80 is a partially enlarged perspective view showing the tread portion and a cross-sectional view showing the proximal notch of the tire according to the sixth embodiment (part 6).

Fig. 81 is a cross-sectional view showing a tire according to a seventh embodiment taken in the tread direction.

BEST MODES FOR CARRYING OUT THE INVENTION The following are examples of a tire according to

The present invention will be described with reference to the drawings. In all drawings, like or similar parts have the same or like reference symbols. It should be noted, however, that the drawings are schematic, and that the dimensional and similar proportions are different from their effective values. Therefore, specific and similar dimensions should be judged based on the description given below. Moreover, there are portions where dimensional relationships and dimensional proportions differ from one drawing to another, of course.

First mode

Tire Configuration

Firstly, with reference to Figures 1 and 2, a description will be given of the configuration of a tire according to a first embodiment. Figure 1 is a partially detailed perspective view of the tire according to the first embodiment. Figure 2 is a cross-sectional view of the tire according to the first embodiment, taken in a tread direction. Note that the tire in this mode is a passenger car radial tire (PCR).

As Figures 1 and 2 show, a tire 1 has a pair of bead parts 3. Each of the bead parts 3 includes at least one bead core 3a, a bead filler 3b, and a bead nail 3c. Tire 1 also has a carcass layer 5 in a toroid shape. Specifically, the carcass layer 5 flexes around each of the bead cores 3a from the inner side in the tread direction to the outer side in the tread direction, and then extends through each one. of the SW side parts.

Side reinforcement layers 7 are formed inwardly in the tread direction of the carcass layer 5 to reinforce the respective side portions SW. The side reinforcement layers 7 are formed in an increasing shape in the cross section taken in the tread direction. An inner liner 9 is provided inwardly in the tread direction of the side reinforcement layers 7. The inner liner 9 is a highly airtight rubber layer which is equivalent to a tube.

A belt layer 11 is provided out in a radial tire direction of the carcass layer 5. The belt layer 11 is formed of a first belt layer 11a, a second belt layer 11b, and a belt layer. of circumferential direction 11c. In each of the first and second belt layers 11a and 11b, codes are arranged inclined with respect to a circumferential direction of the tire. In the belt layer in circumferential direction 11c, codes are arranged substantially parallel to the circumferential direction of the tire.

A tread portion 13 being in contact with a road surface is provided to were, in the radial tire direction, of the belt layer 11. In addition, multiple turbulence-generating bulges (called bulges 17 below) to generate turbulence. are formed on each side of the SW side. The protrusions 17 protrude from a tire surface 15 (which is a surface of the side portion SW).

Bulge Settings

In the following, the configuration (including arrangement and density) of the aforementioned protuberances will be described with reference to Figures 3 to 9. Figures 3 and 4 are main part plan views each showing the arrangement state of the protuberances according to the first one. modality. Figures 5 and 6 are perspective views each showing the protrusion according to the first embodiment. Part (a) of Figure 7 and Figure 8 are side views each showing the protrusion according to the first embodiment seen in the radial direction of the tire (views on arrow A of Figure 5). Part (b) of Figure 7 and Figure 9 are top views each showing the protuberance according to the first embodiment (cross-sectional views B-B of Figure 5).

As Figures 3 to 9 show, each protrusion 17 is formed almost in a cylinder shape having a sharp edge portion E. As Figure 3 shows, protuberances 17 are arranged at predetermined intervals (a gap in circumferential direction p (step ) to be described later) in respective directions: a direction in which turbulence (SI main flow) is generated to flow in a direction opposite to a tire rotation direction and an orthogonal direction to turbulence. In addition, the protuberances 17 in the direction of turbulence generation are arranged in positions offset from one another (in the drawing by offset e / 2). In other words, the protuberances 17 are arranged in a dispersed mode.

Particularly, since the rotation of the tire applies a centrifugal force to the main flow SI, it is preferable, as Figure 4 shows, that a centerline (CL ') in the circumferential protrusion direction inclines with respect to the direction of rotation of the tire at 10 ° to 20 °, with its rear side in the tire rotation direction being outward in the radial tire direction from its front side in the tire rotation direction. Here, the circumferential bulge direction centerline (CL ') is a line that connects the centers of the adjacent bulges 17 in the direction of rotation of the tire. When heat only at the surface of bead portion 3 is to be dissipated, the protuberances 17 may be formed only inwardly in the radial tire direction from a maximum tire width position (i.e., bead portion 3 side) . When, on the other hand, heat only in the vicinity of the belt layer 11 having many layers is to be dissipated, the protuberances 17 may be formed only outward in the radial direction of the tire from the maximum width position of the tire (i.e. tread side 13).

For each of the bulges 17, there is a definite relationship between a tire radius (R) and a maximum bulge height (H). Here, the tire radius (R) is a distance from a rim center to an outermost position in a radial tread direction, and the maximum protrusion height (H) is a protrusion height 17 from from the tire surface 15 to a more protruding position (bulge face 17E) where the bulge 17 protrudes farther from the tire surface 15. Specifically, the ratio 0.015 ^ H / VR ^ 0.64 is satisfied, where "R" is the radius of the tire, and "H" is the maximum bulge height. It is especially preferable to define the tire radius (R) and the maximum protrusion height (H) in the range 0.03 ^ H / VR ^ 0.26.

Here it has been found that the maximum protrusion height (H) should preferably be set to a value between 0.3 mm and 15 mm inclusive (0.3 ^ H ^ 15) to take full advantage of the characteristics and durability of protuberances 17 ( see figure 37). It is especially preferable to define the maximum protrusion height (H) as a value between 0.5 mm and 5 mm inclusive to facilitate temperature dissipation of a basal part T1 (see part 7 (a) of the protuberance). 17 for the tire surface 15, and change in the flow of fluid passing around the protrusion 17.

A maximum protrusion height (H) of less than 0.3 mm is inadequate to alter the flow of fluid passing around the protrusion 17, thereby possibly failing to reduce the tire temperature efficiently. On the other hand, the maximum protrusion height (H) greater than 15 mm is inadequate to suppress a temperature increase at the basal portion T1 of protrusion 17, thereby possibly failing to reduce the tire temperature efficiently.

The tire radius (R) of tire 1 can be obtained by substituting the minimum value (0.3 mm) or the maximum value (15 mm) of the maximum protrusion height (H) in the relative expression 0.015 ^ H / VR ^ 0.64. In other words, from tire radius (R) of tire 1, the minimum value and maximum value of the maximum protrusion height (H) appropriate for that tire 1 can be obtained. Note that the radius of the tire (R) can be, in addition to the passenger car radial tire (PCR), heavy duty tires such as a truck and bus radial tire (TBR) and a construction vehicle radial tire (ORR). ).

Moreover, for protuberances 17, there is a definite relationship between the maximum protrusion height (H) described above and the circumferential protrusion direction range (p). Here, the circumferential bulge steering range (p) is a gap between adjacent bulges 17 in the tire rotational direction. Specifically, the ratio 1.0 ^ p / H ^ 50.0 is satisfied, where "H" is the maximum protrusion height, and "p" is the circumferential protrusion direction range. It is especially preferable to define the maximum protrusion height (H) and the circumferential protrusion direction range (p) in the range of 2.0 ^ p / H ^ 24.0.

As parts (a) and (b) of Figure 10 show, the interval in the circumferential protrusion direction (p) indicates a distance between a point dividing the central width of a protrusion 17 and a point dividing the central width of a protrusion. Therefore, "p / H" is measured at a position on a centerline in the radial bulge (CL) direction which is a line that passes in the center of the width, in the tire rotational direction, of the bulge 17 and is subsequently perpendicular to the tire's direction of rotation. Specifically, the position is in the middle, in the centerline in the radial direction of bulge CL, between positions that are innermost and outermost in the radial tire direction of bulge 17.

If (p / H), namely a ratio of the maximum bulge height ratio (H) to the circumferential bulge direction range (p), is less than 1.0, the turbulence flowing in a substantially perpendicular direction the tire surface 15 (called downflow) does not collide with the tire surface 15 between the protuberances 17. Consequently, the tire temperature cannot be effectively reduced. On the other hand, if (p / H), namely a value of a ratio of the maximum bulge height (H) to the circumferential bulge direction range (p), is greater than 20.0, the turbulence having flowed over a first protrusion 17 reduces its acceleration between protrusions 17. Consequently, the tire temperature cannot be reduced efficiently.

The circumferential bulge direction range (p) can be obtained by substituting the minimum value (0.3 mm) or the maximum value (15 mm) of the maximum bulge height (H) in the relative expression 1.0 ^ p / H ^ 50.0. Therefore, the range in the circumferential protrusion direction (p) and the maximum protrusion height (H) meet the 1.0H ^ p ^ 50.OH ratio. Of course, when the maximum bulge height (H) is the maximum value (ie when the tire radius (R) is large), the range in the circumferential bulge direction (p) is in the range of 15 ^ p ^ 750. .

In addition, for protuberances 17, there is a definite relationship between the maximum protrusion height (H) described above and a protrusion radial direction range (e). Here, the radial bulge steering range (e) is a gap between adjacent bulges 17 in a perpendicular direction of rotation substantially perpendicular to the tire rotation direction. Specifically, the ratio 0.1 ^ H / e ^ 3.0 is met, where "H" is the maximum bulge height, and "e" is the radial radius direction range. The radial protrusion range (e) indicates a distance between an edge portion on the radial protrusion (CL) centerline of a protrusion (17) and an edge portion on the radial direction of radius (CL) bulge (CL) from another bulge 17.

If (H / e), namely a ratio of a ratio of radial bulge direction range (e) to maximum bulge height (H) is less than 0,1, the turbulence flowing in the direction substantially perpendicular to the Tire surface 15 (called downflow) does not collide with tire surface 15 between the protuberances 17. Consequently, the tire temperature cannot be efficiently reduced. On the other hand, if (H / e), namely a value of a ratio of the radial bulge direction range (e) to -the maximum bulge height (H), is greater than 3.0, the turbulence having Fluid over a first protrusion 17 reduces its acceleration between protrusions 17. Consequently, the tire temperature cannot be reduced efficiently.

The radial bulge direction range (e) can be obtained by substituting the minimum value (0.3 mm) or the maximum value (15 mm) of the maximum bulge height (H) in the relative expression 0.1 ^ H / e ^ 3.0 . Therefore, the maximum protrusion height (H) and the radial protrusion direction range (e) meet the ratio 0.1 / H <and ^ 3.O / H.

Moreover, for each of the protuberances 17, there is a definite relationship between the maximum protrusion height (H) described above and a radial protrusion direction length (L). Here, the radial bulge steering length (L) is a maximum bulge length 17 in the perpendicular direction of rotation (radial tire direction). Specifically, the ratio 1.0 ^ L / H ^ 50.0 is met, where "H" is the maximum protrusion height, and "L" is the radial direction length of the protrusion. It is especially preferable to define the maximum protrusion height (H) and the radial protrusion direction length (L) in the range of 1.0 ^ L / H ^ 20.0.

If (L / H), namely a ratio of the ratio of the maximum protrusion height (H) to the radial direction length of protrusion (L), is less than 1.0, the resistance of protrusion 17 is so low. that the bulge 17 is vibrated by turbulence. Consequently, the durability of the protuberance 17 itself deteriorates. On the other hand, if (L / H), namely a ratio of the ratio of the maximum protrusion height (H) to the radial direction length of protrusion (L), is greater than 50.0, protrusion 17 is so long in the perpendicular direction of rotation that the protuberance 17 is inadequate to suppress the temperature increase at the basal portion T1 of the protuberance 17 (see part (a) of figure 7). Consequently, the temperature of the tire cannot be reduced efficiently.

The length in the radial bulge direction (L) can be obtained by substituting the minimum value (0.3 mm) or the maximum value (15 mm) of the maximum bulge height (H) in the relative expression 1.0 ^ L / H ^ 50.0 . Therefore, the maximum protrusion height (H) and the radial protrusion direction length (L) meet the ratio 0.1H ^ L ^ 50.OH. Naturally, when the maximum bulge height (H) is the maximum value (ie when the tire radius (R) is large), the radial bulge steering length (L) is in the range of 15 ^ L ^ 750 .

Further, for protuberances 17, there is a definite relationship between the circumferential protrusion direction range (p) described above and a circumferential protrusion direction length (w). Here, the circumferential bulge steering length (w) is a maximum bulge length 17 in the tire rotation direction. specifically, the ratio 1.0 (p-w) / w ^ 100OO.0 is met, where "p" is the circumferential bulge direction interval, and "w" is the circumferential bulge direction length. It is especially preferable to define the bulge circumferential direction range (p) and the bulge circumferential direction length (w) in the range of 40 ° (p-w) / w ^ 39.0. Here, "p / H" is measured at an average position on the radial bulge direction (CL) centerline between positions which are innermost and outermost in the radial tire direction of the bulge 17.

If the relationship between the circumferential bulge direction range (p) and the circumferential bulge direction length (w) is less than 1.0, a surface area of the bulges 17 is as close as one equivalent to an area of one. region whose heat must be dissipated that the temperature in the bulges 17 (accumulated temperature) cannot be reduced. On the other hand, if the ratio between the circumferential bulge direction range (p) and the circumferential bulge direction length (w) is greater than 100.0, the turbulence having fluid over a first bulge 17 reduces its acceleration between the bulges 17. Consequently, the temperature of the tire cannot be efficiently reduced.

In the following, an average arrangement density (p) of the protuberances 17 will be described with reference to Figure 10. Figure 10 is a schematic top view showing the protuberances according to the first embodiment. Note that the average arrangement density (p) indicates an average density of the protuberances 17 disposed in an area obtained by adding a region between a position 10% of an edge to a position 90% of the edge of a tire height (TH). and a region within each notch 13A formed in the tread portion 13 (in other words, an average density thereof disposed in an area except for the outermost position of the tread contacting a road surface) . Here, the tire height (TH) is a distance from the bead nail 3c to an outermost tread position 13a in a cross section in the tread direction.

An effective heat dissipation region (S) is a region from which heat must be dissipated (or a region that must be cooled) by turbulence generated by a single protuberance 17. As Figure 10 shows, the effective heat dissipation region (S) is obtained such that a value is obtained by adding the protruding radial direction length (L) and the protruding radial direction range (e), and that the value is multiplied by the circumferential protruding direction interval (P). Therefore, the relation S = (L + e) p is satisfied.

The average arrangement density (p) of protuberances 17 is a value of a ratio of the effective heat dissipation region (S) to a single protuberance 17. Therefore, there is a ratio of p = 1 / S. By adding this relational expression to the relational expression described above of the effective heat dissipation region (S), an expression, p = l / (L / e) p, is obtained.

As already described, the circumferential bulge direction range (p) is obtained based on the relative expression 1.0 ^ p / H ^ 50.0. Similarly, a radial radius direction range value (e) is obtained based on the relational expression 0.1 ^ H / e ^ 3.0. Therefore, the inventors have found that by incorporating the circumferential bulge direction range (p) and the radial bulge direction range (e) at p = l / (L / e) p, the bulges 17 have the ratio 1 / {50H (L + 10H)} p <1 / {H (L + H / 3)}.

As described above, the maximum protrusion height (H) and radial protrusion direction length (L) are obtained. The average arrangement density (p) of the protuberances 17 is preferably defined in the range of 0.0008 to 13 pieces / cm2. More preferably, the average arrangement density (p) of the protuberances 17 should be in the range 0.1 to 13 pieces / cm2, and even more preferably in the range 0.5 to 5 pieces / cm2.

When the average arrangement density (p) of the protuberances 17 is less than 0.0008 piece / cm2, an area in which turbulence is generated by the protuberances is so small with respect to the tire surface area 15 that it can hardly be Expect heat dissipation effect from protuberances 17. On the other hand, when the average arrangement density (p) of protuberances 17 is greater than 13 pieces / cm2, protuberances 17 exhibit a more strongly heat accumulating effect than that heat dissipating effect.

The average arrangement density (p) of the protuberances 17 may be uniform over the entire arrangement region. Alternatively, various other arrangement patterns may be employed, including, for example, one in which the average arrangement density (p) gradually decreases from the inner side in the radial direction of the tire towards the outer side in the radial direction of the tire.

Operations and effects according to the first

modality

First, when the tire 1 having the protuberances 17 obtained on the basis of the above relational expression spins, fluid (hereinafter referred to as the main flow SI) flows, as Figure 6 shows, near the tire surface 15 in a direction opposite to the direction of rotation. tire in a relative mode. The main stream Sl then collides with the protuberances 17.

Next, as parts (a) and (b) of Fig. 7 show, the main stream Sl having collided with a front wall face 17a of the protrusion 17 becomes separately flowing turbulent as an upper main stream Sl flowing above a upper wall face 17b and as paired side main flows s2 flowing along the left and right side wall faces 17c, respectively.

Turbulence can be generated because the sharp edge portion E is formed in a portion connecting the front wall face 17a and the bulge face 17E and in a portion connecting the side wall faces 17c and the bulge face 17E. Here, the "sharp" edge does not necessarily have to be sharply pointed, and may be somewhat rounded due to manufacturing processes.

Since the main flow SL flowing above the tire surface 15 becomes turbulence in this way, heat is actively exchanged with the tire surface 15, compared to fluid that flows smoothly and smoothly above the tire surface 16.

With the average arrangement density (p) of protuberances 17 of 0.0008 to 13 pieces / cm2, effective heat dissipation regions S can be created on tire surface 15 over a sufficiently large area. In addition, heat build-up by protrusions 17 may be reduced to some extent.

In addition, the protuberances 17 are arranged in a dispersed mode. Accordingly, even if fluid flowing in the perpendicular direction shifts its course somewhat, the fluid can surely collide with the tire surface 15 in front (the front wall face 17a), in the tire rotational direction, of the protuberance. 17 whereby the fluid flows thereafter. Accordingly, the tire temperature can be further reduced efficiently. In particular, the 10 ° to 20 ° inclination of the bulge circumferential direction (CL ') axis relative to the tire rotation direction allows consideration of the direction in which the main flow Sl flows when the tire rotation applies centrifugal force. .

Accordingly, the interval between the protuberances 17 in the direction of the main flow Sl can be twice as long as the interval between them in the direction orthogonal to the main flow Sl (turbulence). Between the main stream S1 having collided with the protuberance 17, the upper main flow S1 flowing over the protuberance 17 forms downstream downstream of the protuberance 17, as described above. Even if the downstream position somewhat shifts downstream, the upper main stream sl certainly collides with the tire surface 15 before the downstream protrusion 17. Therefore, down flow can certainly effect a temperature reduction.

The following was obtained about the effective heat dissipation region S from both experiments and numerical calculation results. Specifically, as shown in Figure 9, the length of the effective heat dissipation region S formed by a single protrusion 17 is 3H in an orthogonal direction to the main flow SI, ie three times as long as the maximum protrusion height (H ), and is IOH in the direction of the main flow SI, ie ten times as long as the maximum protrusion height (H).

Furthermore, a synergistic effect is not shown when the effective heat dissipation regions S of multiple protuberances 17 overlap one another. Also from a point of view of preventing heat build-up, the number of protuberances 17 should be as small as possible. For these reasons, the protuberances 17 should preferably be arranged by the array density which employs the following ranges: 3H in the orthogonal direction of the main flow Si and IOH in the direction of main flow SI, and more preferably, 2H to 3H in the direction of the orthogonal flow main Sl and 6H to IOH orthogonal to the main flow SI. Such bulge arrangement density 17 exhibits the best heat exchange efficiency.

The fluid temperature gradually increases together with the fluid passing through the protuberances 17, as a centrifugal force causes the fluid to flow obliquely outward in the radial direction of the tire, namely toward the protuberance 17 outwardly in the radial direction. of the tire. Accordingly, the tire temperature can be further efficiently reduced by gradually decreasing the average arrangement density (p) of the protuberances 17 from the inner side in the radial direction of the tire towards the outer side in the radial direction of the tire. This is because, by passing the bulge 17 located on the inner side in the radial direction of the tire, fluid in a low temperature state slightly gains a temperature to have a higher temperature than that in the low temperature state, and then passes through the bulge. 17 located on the outside in the radial tire direction.

When the average arrangement density (p) of the bulges 17, as well as the tire radius (R), the maximum bulge height (H), the circumferential bulge steering range (p), the radial bulge steering range (e), the radial bulge direction length (L), the circumferential bulge direction length (w) meet the above relationships, the main flow travels around the entire bulge circumferential direction range (p) and interval radial steering direction (e) as shown in figure 10. This allows active promotion of heat exchange with the tire surface 15 and a reduction in the heat accumulated in the protuberances 17. Note that the protuberances 17 in figure 10 are schematically shown so that effective heat dissipation regions S can be easily seen.

In addition, the upper main flow sl may have an appropriate separation angle β from protrusion 17 when a front angle (Θ1) is 70 ° to 110 °. In this way, the upper main flow sl becomes downstream, turns to the downstream side of the protuberance 17, and collides with the tire surface 15. Thus, heat is effectively exchanged with the tire surface 15. Consequently, the lumps 17 provided on the tire surface 15 can certainly effect a reduction in tire temperature.

In addition, when an inner angle (Θ3) and an outer angle (Θ4) are set at a value between 70 ° and 110 °, inclusive, between the main flow colliding with the protrusion 17, the lateral main flows s2 flowing at the sides. of the protuberance 17 form return flow on the downstream side of the protuberance 17. Thus, the effective heat dissipation region S in which a certain heat dissipation effect can be expected is formed around the protuberance 17, and heat buildup of protrusion 17 may be reduced. Accordingly, the protrusions 17 provided on the tire surface 15 can certainly effect a reduction in tire temperature.

Since the protrusions 17 are individually approximately cylindrical in shape, the inner angle (externo3) and the outer angle (Θ4) are defined at the same angle as the front angle (definidos1), namely in the range of 70 ° to 110 °. However, the inside angle (Θ3) and outside angle (Θ4) can be set at a different angle from the front angle (Θ1) as long as they fall within the range of 70 ° to 110 °.

Additionally, the side reinforcement layers 7 are provided, and the protrusions 17 are formed on the side portions SW. In this way, the tire temperature can be effectively reduced in a part where a temperature is expected to rise dramatically by deformation or the like (for example, a part out of the side reinforcement layer in a punctured state). Therefore, durability can also be improved.

Modification 1 according to the first embodiment In the above description of the protuberance 17, according to the first embodiment, the protuberance 17 is formed almost like a cylinder. However, the following modifications can be made. Note that the same parts as those of protrusion 17 according to the first embodiment described above contain the same reference symbols, and different points are mainly described.

Figure 11 is a perspective view showing a protrusion of Modification 1 according to the first embodiment. As Figure 11 shows, a protrusion 17a is shaped like a square pole. Note that the protrusion 17 may employ various shapes other than cylinder shape and square pole shape. Such alternative formats will be described in the second embodiment and subsequent embodiments below.

EXAMPLES ACCORDING TO FIRST MODE Bulk Arrangement Density Experiments

The protrusions are individually made of rubber and molded primarily as a cylinder or a square pole. The prepared protuberances had the radial protrusion (L) steering length of various sizes in the range of 0.3 mm to 15 mm. The following experimental method was employed. Specifically, the aforementioned protuberances were arranged in a flat heater which emits a constant amount of heat, and the surface thereof was supplied with air by a blower. A heat transfer coefficient was calculated from the surface temperature and atmospheric temperature acquired at that time. Thus, the characteristic graph shown in figure 12 was obtained with the heat transfer coefficient of a flat plate having no protuberances being evaluated as 100.

The inventors have found that the heat transfer coefficient improves markedly when the average arrangement density (p) of protuberances 17 meets the ratio 1 / {50H (L + 10H)} ^ ρ <1 / {H (L + H / 3 )}. Specifically, as Figure 12 shows, the average arrangement density (p) that achieves the heat transfer coefficient improvement of 130 is in the range of 0.0008 to 13 pieces / cm2. It was confirmed that the tire temperature was reduced by the bulges 17 with the average arrangement density (p) in this range.

Note that Figure 12 shows the average arrangement density (p) of each case (aaf) where the radial protrusion length (L) is 0.3 mm, 0.5 mm, 2 mm, 5 mm, 10 mm, and 15 mm, respectively.

Next, a durability test was performed using turbulence generation protuberances having different H / VR, p / H, H / e, L / H, (p-w) / w, and tilt angles of the dispersed array.

The results are shown in figures 13 to 18. The longitudinal geometric axis of each graph shown in figures 13 to 18 is the heat transfer coefficient obtained by measuring the temperature of the tire surface at which a certain amount of heat emitted by a heater. applied with a constant voltage was being blown by a blower. Therefore, the higher the heat transfer coefficient, the higher the cooling effect and durability. Here, the heat transfer coefficient of a tire supplied without bulges (conventional example) is set to "100".

Note that data on each tire was acquired by measurement under the following conditions.

Tire Size: 285 / 50R20

Wheel size: 8JJx20

Internal pressure condition: OkPa (in one state

bored)

Charging condition: 0.5 kN

Speed condition: 90 km / h

As Figure 13 shows, the heat transfer coefficient improves when the ratio of tire radius ® to maximum bulge height (H) meets 0. 015 ^ H / a / R ^ 0. 64. Therefore, it has been found that the maximum bulge height (H) should preferably be set based on the size of the tire. Especially, Figure 13 shows that the maximum protrusion height (H) should preferably be defined within the range of 0.03 ^ H / VR ^ 0.26.

As Figure 14 shows, the heat transfer coefficient improves when (w / H), namely the relationship between the maximum protrusion height (H) and the circumferential protrusion direction range (p), satisfies 1.0 m / w 50.0. Especially, by setting w / H in the range of 2.0 ^ w / H ^ 24.0, the heat transfer coefficient improves more, and better durability is obtained.

As Figure 15 shows, the heat transfer coefficient improves when (H / e), namely, the relationship between the maximum protrusion height (H) and the radial protrusion direction range (e) satisfies 0.1 <H / e <3.0.

As Figure 16 shows, the heat transfer coefficient improves when (L / H), namely the relationship between the maximum protrusion height (H) and the length in the radial protrusion direction (L) ', meets 1.0 ^ L / H <50.0. Especially by setting L / H in the range of 1.0 ^ L / H ^ 20.0, the heat transfer coefficient improves more, and better durability is obtained.

As Figure 17 shows, the heat transfer coefficient improves when the ratio between (p- w) / w and a heat transfer coefficient (measured by the same method as the heat transfer coefficient described above) is defined in the range 1.0 <(p- w) / w <100.0. Especially by setting the ratio in the range of 4. (p-w) / w ^ 39.0, the heat transfer coefficient improves more, and better durability is obtained.

A centrifugal force generated by the rotation of the tire accelerates the main flow. Therefore, as Figure 18 shows, the heat transfer coefficient improves by the 10 ° to 20 ° inclination of the circumferential bulge (CL ') center line with respect to the tire's direction of rotation with its rear end in the tire rotation direction being shifted outward in the radial direction of tire from the front in the tire rotation direction. Next, experiments were performed on the bulge width and angle of the bulge front wall face. The protrusions were cylindrical in shape, and had a radial protrusion length (L) of 2 mm, the maximum protrusion height (H) of various sizes in the range 0.3 to 15 mm, the wall face angle (Θ) each between the front wall face and the side wall faces (the front angle Θ1, the inner angle externo3, and the outer angle Θ4) of 90 °, and the arrangement density (p) of 0, 8 piece / cm2.

Data on each tire was acquired by measurement under the following conditions.

Tire Size: 285 / 50R20

Wheel size: 8JJx20

Internal pressure condition: OkPa (in one state

bored)

Loading condition: 9.8 kN

Each of the tires was fitted into a drum tester placed inside, rotated at a constant speed (90 km / h), and measured for its durable distance to breakage. Durable tire distance has no lumps 17 was set to 100. Then the durability of each tire having lumps 17 was evaluated as a relative value to 100. Note that the higher the index, the better the durability, namely , the better the temperature reduction characteristics.

Table 1 Radial Direction Length --- 1 2 10 50 70 100 Bulge Height L [ram] Bulge Height H --- 2 2 2 2 2 2 [mm] Average Arrangement Density p --- 2 2 2 2 2 2 [piece / cm2] Wall face angle Θ [*] - 90 90 90 90 90 90 90 L / H - 0.5 1.0 5.0 25.0 35.0 50, 0 Durability 100 101 113 135 137 132 112 Table 2

Radial direction length of 2 2 2 2 2 Protrusion L [mm] Protrusion height H [mm] - 2 2 2 2 2 Wall face angle Θ [*] --- 4.5 70 90 110 135 Average mass density arrangement p 0.8 0.8 0.8 0.8 0.8 [piece / cm2] Durability 100 101 120 133 113 102 As Table 1 shows, it was confirmed that the

durability (heat dissipation characteristics) improved when the ratio 1.0 <L / H <50.0 was satisfied.

As Table 2 shows, it was experimentally confirmed that bulges improved durability (heat dissipation characteristics) when each of the wall face angles Θ (the front angle Θ1, the inner angle Θ3, and the outer angle Θ4) was. set in the range 70 ° to 110 °.

Second modality

In the following, the configuration of a protrusion 17 according to a second embodiment will be described with reference to figures 19 and 20. Note that the same parts as those of tire 1 according to the first embodiment described above contain the same symbols. reference, and different parts will be mainly described. Namely, points such as tire configuration 1 and arrangement and arrangement density of protuberances 17 are not repeatedly described. However, some points may be partially repeated.

Figure 19 is a perspective view showing a protrusion according to the second embodiment. Part (a) of Fig. 20 is a top view showing the protrusion according to the second embodiment (a view which is seen on arrow A of Fig. 19). Part (b) of the figure is a cross-sectional view showing the protrusion according to the second embodiment viewed in the radial direction of the tire (a cross-sectional view B-B of figure 19). Part (c) of Fig. 20 is a front view showing the protrusion according to the second embodiment seen in the direction of rotation of the tire (a view that is seen on arrow C of Fig. 19).

As Figures 19 and 20 show, the protrusion 17 is formed of: an inner face 17A (inner part) located in an innermost position in the radial direction of the tire; an outer face 17B (outer) located at a more external position in the radial direction of the tire; a front face 17C located forward, in the direction of rotation of the tire, of the protruding radial direction centerline CL; a rear face 17D located rearwardly in the direction of rotation of the tire from the centerline in the radial direction of bulge CL; and a protruding face 17E protruding from the tire surface 15.

The bulge 17 is formed in a parallelogram in a radial direction view of the tire, which is a view in which the bulge 17 is viewed in the radial direction of the tire (see part (b) of figure 20). The protrusion 17 is also formed on a parallelogram in a view in the tire rotation direction, which is a view in which the protrusion 17 is viewed from the front side in the tire rotation direction (see Figure (c) of the figure). 20).

Accordingly, the protrusion 17 has an edge portion E which is formed by a portion connecting the inner face 17A and the protruding face 17E, a portion connecting the outer face 17B and the protruding face 17È, a portion connecting the front face 17C and bulge face 17E, and a portion that connects rear face 17D and bulge face 17E.

As part (a) of Fig. 20 shows, the inner face 17A, the outer face 17B, the rear face 17D, and the bulge face 17E are formed to be flat. The front face 17C curves toward the front side in the tire's direction of rotation.

Specifically, the inner face 17A and the outer face 17B are formed substantially perpendicular to the protruding radial direction centerline CL. The rear face 17D is formed substantially parallel to the protruding radial direction centerline CL. The bulge face 17E is formed substantially parallel to the tire surface 15.

As part (b) of Figure 20 shows, a front angle (Θ1) formed between the front face 17C and the tire surface 15 and a rear angle (Θ2) formed between the rear face 17D and the tire surface 15 are individually defined. between 45 ° and 135 ° inclusive. It is especially preferable to set the front angle (Θ1) and rear angle (Θ2) to between 70 ° and 110 ° inclusive to reduce tire temperature efficiently.

Front angle (Θ1) and rear angle (Θ2) less than 45 ° could stop fluid flow above the tire surface 15 (on the heat dissipating surface), which could not generate a pressure difference to accelerate. fluid flow. On the other hand, the front angle (Θ1) and rear angle (Θ2) greater than 135 ° are inadequate to change the flow of fluid passing around the protrusion 17. Consequently, the tire temperature might not be able to be reduced efficiently.

As part © of Figure 20 shows, an inner angle (Θ3) formed between the inner face 17A and the tire surface 15 and an outer angle (Θ4) formed between the outer face 17B and the tire surface 15 are individually defined in. a value between 45 ° and 135 ° inclusive. It is especially preferable to set the inside angle (Θ3) and outside angle (Θ4) to between 70 ° and 110 ° inclusive to efficiently reduce the tire temperature.

The inside angle (Θ3) and outside angle (Θ4) of less than 45 ° could stop fluid flow above the tire surface 15 (on the heat dissipating surface), which could not generate a pressure difference to accelerate the flow. fluid flow. On the other hand, the inside angle (Θ3) and outside angle (Θ4) greater than 135 ° are inadequate to change the flow of fluid passing around the protuberance 17. Consequently, the tire temperature might not be able to be reduced efficiently.

Operations and effects according to the second

modality

According to tire 1, according to the second embodiment described above, the protuberance 17 has the edge portion E, and the average arrangement density (p) of the protuberances 17 is 0.1 to 13 pieces / cm2. In this way, tire 1 can efficiently reduce tire temperature while maintaining overall steering performance.

Specifically, the curved front face 17C, and the front angle (Θ1) and rear angle (Θ2) are individually set to a value between 45 ° and 135 ° inclusive. Such shape and angles allow pressure to increase on the front side, in the direction of rotation of the tire, of the protrusion 17 (the front face 17C). This increase in pressure may accelerate the flow of fluid passing around the protrusion 17 (namely, it may improve the heat dissipation rate of the tire temperature). Thus, without a new breakdown, tire 1 can efficiently reduce tire temperature while maintaining overall driving performance.

More specifically, as Figure 21 shows, as tire 1 rotates, protrusion 17 causes fluid (called a main flow Sl below) in contact with tire surface 15 (the side portion SW) to separate from the SW side part. Then the main flow SL flows over the edge E (the front side edge) of the protrusion 17 and accelerates towards the rear side of the tire rotation direction (namely rearward).

Then, the accelerated main flow SL thus flows in a direction perpendicular to the tire surface 15 on the rear side of the rear face 17D. At this time, fluid S3 flows a part (region) where fluid flow remains, thereby drawing heat remaining on the rear side of rear face 17D, and then again merging with main flow SI.

Main stream S1 flows over edge E and thereby accelerates, and fluid S3 pulls heat and then merges again with main stream S1. This allows for a temperature reduction over a large area of the tire. In particular, a temperature may be reduced at a basal portion T1 of the protuberance 17 and in a region T2 where the main flow SL contacts in the perpendicular direction.

In addition, the protuberances 17 are arranged in a dispersed mode. Accordingly, even if fluid flowing in the perpendicular direction somewhat displaces its path, the fluid can surely collide with the tire surface 15 on the front side (the front face 17C), in the direction of tire rotation, of the protrusion 17. whereby the fluid flows thereafter. Consequently, the tire temperature can be further reduced efficiently.

Centrifugal force causes fluid to flow obliquely outward in the radial direction of the tire, namely toward the protrusion 17 located outwardly in the radial direction of the tire. The temperature of the fluid gradually increases as the fluid passes through the protuberances 17. Therefore, the tire temperature can be further efficiently reduced by gradually decreasing the average arrangement density (p) of the protuberances 17 from the inner side of the tire. radial tire direction towards the outside in the radial tire direction. This is because, by passing a bulge 17 located on the inner side in the radial direction of the tire, fluid in a low temperature state slightly gains a temperature to have a higher temperature than in the low temperature state, and then passes through. a protrusion 17 located on the outside in the radial direction of the tire.

In addition, when the maximum protrusion height (H) is set to a value between 0.3 mm and 15 mm inclusive, an increase in temperature at the basal portion T1 of protuberance 17 may be suppressed. In addition, the flow of fluid passing around the protrusion 17 may be further accelerated.

Additionally, the front angle (Θ1) and rear angle (Θ2) are set to a value between 45 ° and 135 ° inclusive. Thus, fluid flow having collided with the front face 17C may increase a pressure on the front face 17C. This pressure increase can further accelerate the flow of fluid passing around the protuberance 17.

In addition, the inside angle (Θ3) and outside angle (Θ4) are set to a value between 45 ° and 135 ° inclusive. Thus, when fluid separates from (spreads around) the bulge 17 by colliding with the front face 17C, the flow of fluid thereby spreading around the bulge 17 can certainly be accelerated.

Modification 1 according to the second mode

In the above description of the protrusion 17, according to the second embodiment, the front face 17C forming the protrusion 17 is formed as a single face. However, the following modifications can be made. Note that the same parts as those of protrusion 17 according to the second embodiment described above contain the same reference symbols, and different points are mainly described.

Figure 22 is a top view showing a protrusion of Modification 1 according to the second embodiment. As part (a) of Fig. 22 shows, in a top view of the protuberance, which is a view in which protuberance 17 is viewed from the top, the protuberance is provided with two front convex portions 17C-1 and a single front concave portion. 17C-2 forward, in the direction of tire rotation, from the radius of the radius direction CL. The front convex portions 17C-1 and the front concave portion 17C-2 are individually formed into a curve. Therefore, the front face 17C is at least partially curved.

Although described above as such, the protrusion 17 is not limited to being provided with two front convex portions 17C-1 and the single front concave portion 17C-2 forward, in the direction of tire rotation, of the radial protrusion centerline CL. As shown in part (b) of Fig. 22 for example, three front convex portions 17C-1 and two front concave portions 17C-2 may be provided. There is no limitation provided that at least any one between the front convex portion 17C-1 and the front concave portion 17C-22 is provided.

According to tire 1 of Modification 1 according to the second embodiment, the flow of fluid passing around the protrusion 17 may be gently accelerated. In this way the tire temperature can be reduced efficiently.

Modification 2 according to the second mode

In the above description, the rear face 17D of the protrusion 17 according to the second embodiment is formed substantially parallel to the protruding radial direction centerline CL. However, the following modifications can be made. Note that the same parts as those of protrusion 17 according to the second embodiment described above contain the same reference symbols, and different points are mainly described.

Fig. 23 is a perspective view showing a protrusion of Modification 2 according to the second embodiment. Part (a) of Fig. 24 is a top view showing the protrusion of Modification 2 according to the second embodiment (a view which is seen on arrow A of Fig. 23). Part (b) of Fig. 24 is a cross-sectional view showing the bulge of Modification 2 according to the second embodiment viewed in the radial direction of the tire (a cross-sectional view B-B of Fig. 23). Part (c) of Fig. 24 is a front view showing the bulge of Modification 2 according to the second embodiment seen in the direction of tire rotation (a view which is seen on arrow C of Fig. 23).

As figures 23 and 24 show, in a top view of the protuberance, the protuberance is provided with two rear convex portions 17D-1 and a single rear concave portion 17D-2 rearward, in the direction of tire rotation, of the centerline. protruding radial direction CL. The rear convex portions 17D-1 protrude backward in the tire rotation direction, and the rear concave portion 17D-2 is concave in the tire rotation direction. As part (a) of Fig. 24 shows, the rear convex portions 17D-1 and the rear concave portion 17D-2 are linearly formed.

Although described above as such, the protrusion 17 is not limited to being provided with the rear convex portions 17D-1 and the rear concave portion 17D-2 rearward in the tire rotation direction of the radial protrusion axis CL. As shown in part (a) of Fig. 25 for example, only the rear convex part 17D-1 may be provided. There is no limitation provided that at least any of the 17D-1 rear convex portion and the 17D-2 rear concave portion is provided.

In addition, although described above as such, the protrusion 17 is not limited to being provided with the two rear convex portions 17D-1 and the single rear concave portion 17D-2 rearward, in the direction of tire rotation, of the steering centerline. radial protrusion CL. As shown in part (b) of Figure 25 for example, three rear convex portions 17D-1 and two rear concave portions 17D-2 may be provided.

Furthermore, although described above as such, the rear convex portion 17D-1 and the rear concave portion 17D-2 are not limited to being linearly formed. For example, the following modifications may of course be made. Specifically, as part © of Figure 25 shows, only the rear convex portion 17D-1 can be formed into a curve. As part (d) of Fig. 25 shows, three rear convex portions 17D-1 individually having a curved end and two rear concave portions 17D-2 individually having a curved end can be formed into a curve. As part (e) of Figure 25 shows, the rear concave portion 17D-2 may be formed into a curved shape between two rear convex portions 17D-1.

According to tire 1 of Modification 2 according to the second embodiment, the rear convex portion 17D-1 is provided rearward, in the tire rotational direction, of the radial radial direction centerline CL. Therefore, backward flowing fluid can be smoothly returned to the main flow. In this way the tire temperature can be reduced efficiently.

In addition, the provision of the rear concave part 17D-2 to the rear, in the tire rotation direction, of the radius of the radius of direction CL makes the volume of the bulge 17 smaller and the distance between the basal part of the bulge 17 and the 15 shorter tire surface. Thus, an increase in temperature at the basal part of the protuberance 17 can be suppressed.

Additionally, by providing the rear convex portion 17D-1 and the rear concave portion 17D-2 to the rear, in the tire rotational direction, of the radial radius CL direction axis, not only can the fluid flow passing around it of the protuberance 17 being accelerated, an increase in temperature at the basal part of the protuberance 17 may be suppressed. Consequently, the tire temperature can be reduced more efficiently.

Modification 3 according to the second mode

In the above description of the protuberance 17, according to the second embodiment, the protuberance 17 is formed in a parallelogram viewed in the radial tire direction. However, the following modifications can be made. Note that the same parts as those of protrusion 17, according to the second embodiment described above, contain the same reference symbols, and different points are mainly described.

26 is a perspective view showing a protrusion of Modification 3 according to the second embodiment. Part (a) of Fig. 27 is a top view showing the protrusion of Modification 3 according to the second embodiment (a view which is seen on arrow A of Fig. 26). Part (b) of Fig. 27 is a side view showing the bulge of Modification 3 according to the second embodiment viewed in the radial direction of tire (a view which is seen on arrow B of Fig. 26). Part (c) of Fig. 27 is a front view showing the bulge of Modification 3 according to the second embodiment seen in the direction of tire rotation (a view that is seen on arrow C of Fig. 26).

As Figures 26 and 27 show, the protrusion 17 is formed of the inner face 17A, outer face 17B, and boss face 17E. The bulging face 17E bends. Accordingly, the protrusion 17 is formed into a semi sphere when viewed in the radial direction of the tire.

As part (a) of Fig. 27 shows, the maximum protrusion height (H) according to this embodiment is a height from the tire surface 15 to a more projected position 21 where protrusion 17 is

projects farther from the tire surface 15.

As part (b) of Figure 27 shows, a maximum front angle (Θ5) and a maximum rear angle (Θ6) are individually set to a value between 45 ° and 135 ° inclusive. It is especially preferred to define the angle

front maximum (Θ5) and rear maximum angle (Θ6) by up to and including 70 ° and 110 ° to efficiently reduce tire temperature.

Here the maximum front angle (Θ5) is an angle formed between an intersecting position 23 of a portion

19A and the tire surface 15, and the most projected position 21. The rear maximum angle (Θ6) is an angle formed between an intersection position 25 of a rear 19B and the tire surface 15, and the most projected position 21. Here, the rear part 19B is located on the

rearward side, in the direction of tire rotation, of the radial direction centerline of the bulge CL.

Front maximum angle (Θ5) and rear maximum angle (Θ6) less than 45 ° could stop fluid flow on tire surface 15 (on tire surface).

heat dissipation), which could not generate a pressure difference to accelerate fluid flow. On the other hand, the maximum front angle (Θ5) and rear maximum angle (Θ6) greater than 135 ° are inadequate to change the flow of fluid passing around the protuberance 17.

Consequently, the tire temperature might not be able to be reduced efficiently. Although described above as such, the bulge 17 is not limited to being formed in a semi sphere when viewed in the radial tire direction. For example, the following modifications can be made. Specifically, as Figure 28 shows, the protrusion 17 may be formed into a

triangle when viewed in the radial direction of the tire. As Figure 29 shows, the protrusion 17 may be formed into a trapezoid when viewed in the radial direction of the tire. Here, "the trapezoid has an underside (the underside of the protrusion 17, which is in contact with the

tire 15) wider than bulge face 17E. Moreover, as Figure 30 shows, the protrusion 17 may be formed into a trapezoid when viewed in the radial tire direction. Here the trapezoid has a narrower underside than the bulge face 17E.

According to the tire 1 of Modification 3 according to the second embodiment, the flow of fluid passing around the protrusion 17 may be gently accelerated. In this way the tire temperature can be reduced efficiently.

In addition, by setting the maximum front angle (Θ5) and the maximum rear angle (Θ6) to a value between 45 ° and 135 ° inclusive, fluid flow having collided with front side 19A (the front side of protrusion 17E) may increase a pressure near the front 19A.

Thus, the. fluid flow passing around the protrusion 17 may be further accelerated.

Modification 4 according to the second embodiment In the above description of the protuberance 17, according to the second embodiment, the protuberance 17 is formed in

a parallelogram when viewed in the direction of tire rotation. However, the following modifications can be made. Note that the same parts as those of protrusion 17 according to the second embodiment described above contain the same reference symbols, and different points are mainly described.

Fig. 31 is a perspective view showing a protrusion of Modification 4 according to the second embodiment. Part (a) of Fig. 32 is a top view showing the protrusion of Modification 4 according to the second embodiment (a view which is seen on arrow A of Fig. 31). Part (b) of Fig. 32 is a cross-sectional view showing the protrusion of Modification 4 according to the second embodiment viewed in the radial direction of the tire (a cross-sectional view B-B of Fig. 31). Part (c) of Fig. 32 is a front view showing the bulge of Modification 4 according to the second embodiment seen in the direction of tire rotation (a view that is seen on arrow C of Fig. 31).

As figures 31 and 32 show, the protrusion 17 is formed of the front face 17C, the rear face 17D and the protrusion face 17E. The bulging face 17E bends. Accordingly, the protrusion 17 is formed into a semi sphere when viewed in the direction of tire rotation.

As part (a) of Fig. 32 shows, the maximum protrusion height (H) according to this embodiment is a height from the tire surface 15 to a more projected position 27 where protrusion 17 protrudes farther. of the tire surface 15.

As part (c) of Figure 32 shows, an internal maximum angle (Θ7) and an external maximum angle (Θ8) are individually set to a value between 45 ° and 135 ° inclusive. It is especially preferable to set the maximum internal angle (Θ7) and maximum external angle (Θ8) to a value between 70 ° and 110 ° inclusive to efficiently reduce the tire temperature. Here, the inner maximum angle (Θ7) is an angle formed between an intersecting position 29 of an inner part 19C and the tire surface 15, and the most projected position 27. Here, the inner part 19C is located at the innermost position. in the radial direction of tire. The outer maximum angle (Θ8) is an angle formed between an intersecting position 31 of an outer 19D and the tire surface 15, and the most projected position 27. Here, the outer 19D is located in the outermost position in the direction tire radial.

The maximum internal angle (Θ7) and maximum external angle (Θ8) of less than 45 ° could stop fluid flow above tire surface 15 (on the heat dissipation surface), which could not generate a pressure difference for accelerate fluid flow. On the other hand, the internal maximum angle (Θ7) and the maximum external angle (Θ8) greater than 135 ° are inadequate to change the flow of fluid passing around the protuberance 17. As a result, the tire temperature might not be capable. be reduced efficiently.

Although described as such, the bulge 17 is not limited to being formed in a half sphere when viewed in the direction of tire rotation. For example, the following modifications can be made. Specifically, as Figure 33 shows, the protrusion 17 may be formed into a triangle when viewed in the direction of tire rotation. As figure 34 shows, the protrusion 17 may be formed into a trapezoid when viewed in the direction of tire rotation. Here, the trapezoid has a broader underside than the bulge face 17E. In addition, as Figure 35 shows, the protrusion 17 may be formed into a trapezoid when viewed in the direction of tire rotation. Here the trapezoid has a narrower underside than the bulge face 17E.

According to tire 1 of Modification 4 according to the second embodiment, the flow of fluid passing around the protrusion 17 may be gently accelerated. In this way the tire temperature can be reduced efficiently.

In addition, the maximum internal angle (Θ7) and maximum external angle (Θ8) are set to a value between 45 ° and 135 ° inclusive. Thus, when fluid spreads around the protuberance 17 by colliding with the front face 17C, the flow of fluid thereby separating from (spreading around) the protuberance 17 can certainly be accelerated.

EXAMPLES ACCORDING TO SECOND MODE

Next, to further clarify the effects of the invention according to the second embodiment, the results obtained from tests performed using the following tires will be described. It should be noted that these examples in no way limit the present invention.

Data on each tire was acquired by measurement under the following conditions.

Tire Size: 285 / 50R20

Wheel size: 8JJx20

Internal pressure condition: OkPa (in one state

bored)

Loading condition: 9.8 kN

As shown in the following tables 3 to 6, test tires A, test tires B, test tires C, and test tires D have been prepared to test the durability of each of these tires. The tires according to comparative examples 1 to 4 have no protrusions. The tires according to examples 1 to 36 have bulges and have different bulge configurations (such as shapes, radial bulge steering length (L), and maximum bulge height (H)) as shown in the following tables. 3 to 6. TABLE 3 Test Tire A Example Example Example Example Example Example Example Example Example Comparative Example 1 2 3 4 5 6 7 8 9 1 Top View Bulge OCS1 (top) View from o * n £> «àflí * radial tire direction (side) View from 9Siya ΊΓΦ« * i * £ $ * IW tire rotation direction (front) Length of 0.4 2 8 2 2 2 2 2 2 radial direction height (L) Maximum height 2 2 2 0.4 8 2 2 2 2 height (H) Θ1, Θ2 --- 90 90 90 90 90 50 130 90 90 (degrees) Θ3, Θ4 ““ 90 90 90 90 90 90 90 90 50 130 (degrees) Durability 100 101 135 102 105 108 107 105 105 104 TABLE 4 Test tire B Example Example Example Example Example Example Example Example Example Comparative example 10 11 12 13 14 15 16 17 18 2 Top view ΦΟ protrusion (top) W view Radial direction • tire length (side) View from • arr srr IW tire rotation direction (front) Length 0.4 2 8 2 2 2 2 2 2 radial steering direction (L) Maximum height 2 2 2 0,4 8 2 2 2 2 of protuberance (H) Θ1, Θ2 --- 90 90 90 90 90 50 130 90 90 (degrees) Θ3, Θ4 --- 90 90 90 90 90 90 90 50 130 ( degrees) Durability 100 101 136 108 105 112 108 105 106 104 TABLE 5 Test tire C Example Example Example Example Example Example Example Example Example Example compar active 19 20 21 22 23 24 25 26 27 3 Top view and> 0J of r% tm> Il1Ilil 'bulge (top) View of OiJTfiO1 radial tire direction (side) Wt • re direction of tire rotation (front) Length 0.4 2 8 2 2 2 2 2 2 protu¬ berância radial direction (U) Maximum Height 0.4 8 2 2 2 2 2 2 2 protu¬ berância (H) 1, Θ2 90 90 90 90 90 50 50 90 90 (degrees) Θ3, Θ4 90 90 90 90 90 90 90 50 50 130 (degrees) Durability 100 101 133 109 104 111 107 104 105 102 TABLE 6 Test tire D Example Example Example Example Example Example Example Example Example Comparative Example 28 29 30 31 32 33 34 35 36 4 Top View protrusion (top) View of tSJp W eJHi1 radial tire direction (side) Trr W IW view tire rotation direction (front) Length 0/4 2 8 2 2 2 2 2 2 Radial guarding direction (L) Maximum height 2 2 2 0,4 8 2 2 2 2 guarding (H) Θ1, Θ2 90 90 90 90 90 50 130 90 90 (degrees) Θ3, Θ4 --- 90 90 90 90 90 90 90 50 130 (degrees) Durability 100 101 133 109 104 111 107 105 106 104 56/95 Durability Each tire was fitted into a drum tester placed inside, rotated at constant speed (90 km / h), and was measured against its durable distance to breakage. The tire durability of each of comparative examples 1 to 4 was set to '100'. Then, the durability of each of the other tires was rated at a value of 100. Note that the higher the index, the better the durability.

As a result, as shown in Tables 3 to 6, it has been found that tires according to Examples 1 to 36 have excellent durability compared to tires according to Comparative Examples 1 to 36.

4. Particularly, as shown in Figure 36, it has been found that the tire that meets the ratio 1.0 <L / H <50.0 has excellent durability. Also, as shown in Figure 37, it has been found that the tire having the maximum protrusion height (H) of 0.3 mm to 15 mm has excellent durability.

Third modality

In the following, the configuration of a protrusion 17 according to a third embodiment will be described with reference to figures 38 and 39. Note that the same parts as those of tire 1 according to the first embodiment described above contain the same symbols. reference, and different parts will be described primarily. Namely, points such as tire configuration I and arrangement and arrangement density of protuberances 17 are not described repeatedly. However, some points may be partially repeated.

Fig. 38 is a perspective view showing the protrusion according to the third embodiment. Part (a) of Fig. 39 is a top view showing the protrusion according to the third embodiment (a view which is seen on arrow A of Fig. 38). Part (b) of Fig. 39 is a cross-sectional view showing the protrusion according to the third embodiment viewed in the radial direction of tire (a cross-sectional view B-B of Fig. 38). Part (c) of Fig. 39 is a front view showing the protrusion according to the third embodiment seen in the direction of tire rotation (a view that is seen in arrow C of Fig. 38).

As figures 38 and 39 show, the protrusion 17 is formed of an inner face 17A, an outer face 17B, two front faces 17C, a rear face 17D, and a protrusion face 17E. '

As part (a) of Fig. 39 shows, in a top view of the protrusion, the protrusion is provided with a front convex portion 37 forward in the tire rotation direction of the radial protrusion axis CL. Front convex portion 37 projects in the direction of tire rotation in a triangle. The two front faces 17C form the front convex portion 37 and are the same size.

In a top view of the protrusion 17, each between inner face 17A, outer face 17B, front faces 17C and rear face 17D is linearly formed (flattened). As part (b) of Fig. 39 shows, the protrusion 17 is formed in a parallelogram when viewed in the radial tire direction. As part (c) of Fig. 39 shows, the protrusion 17 is formed in a parallelogram when viewed also in the direction of tire rotation.

Thereby, the inner face 17A and the outer face 17B are formed substantially perpendicular to the protruding radial direction centerline CL. The rear face 17D is formed substantially parallel to the protruding radial direction centerline CL. In addition, the bulge face 17E is formed substantially parallel to the tire surface 15.

As part (b) of Fig. 39 shows, a front angle (Θ1) and a rear angle (Θ2) are individually set between 45 ° and 135 ° inclusive. It is especially preferred to set the front angle (Θ1) and rear angle (Θ2) to between 70 ° and 110 ° inclusive.

As part (c) of Fig. 39 shows, an inner angle (Θ3) and an outer angle (Θ4) are individually set to a value between 45 ° and 135 ° inclusive. Especialmente It is especially preferable to set the inside angle (Θ3) and outside angle (Θ4) to a value between 70 ° and 110 ° inclusive to reduce tire temperature efficiently.

Operations and effects according to the third

modality

According to pneumatic 1, in accordance with the third embodiment described above, the front convex portion 37 is provided forward, in the tire rotational direction, of the radial radial direction centerline CL. This allows a pressure to increase on the front side (front face 17C) in the direction of tire rotation of the protrusion 17. This pressure increase can accelerate the flow of fluid passing around the protrusion 17 (i.e., it can improve a heat dissipation rate of tire temperature). Thus, without a new breakdown, tire 1 can efficiently reduce tire temperature while maintaining overall driving performance. More specifically, as Figure 40 shows, as tire 1 rotates, protrusion 17 causes fluid (called a main flow Sl below) to contact tire surface 15 (the side portion SW).

separate from the side of SW. So the main stream Sl

it flows over an edge E of bulge 17 and accelerates towards the rear side in the direction of tire rotation (namely rearward).

Here, by the acute front convex portion 37 provided forward in the tire rotation direction of the

protruding radial direction centerline CL, the main stream Sl is, before flowing over edge E, separated from an apex at which both front faces 17C intersect. In this way, the main stream Sl is accelerated as it flows over edge E.

The thus accelerated main flow SL flows in a direction perpendicular to the tire surface 15 on the rear side of the rear face 17D. At that time, fluid S3 flows a part (region) where fluid flow remains, thereby drawing heat that remains on the rear side of the fluid.

rear face 17D, and then merges again with main flow SI.

As described, the main stream Sl flows over the edge E and thereby accelerates, and the fluid S3 pulls heat and then merges again with the main stream Si.

allows a temperature reduction over a large area of the tire. In particular, a temperature may be reduced at a basal portion T1 of the protuberance 17 and in a region T2 where the main flow SL contacts in the perpendicular direction.

Modification 1 according to the third mode

In the above description of the protrusion 17, according to the third embodiment, the front faces 17C constituting the protrusion 17 are the same size. However, the following modifications can be made. Note that the same parts as those of protrusion 17 according to the third embodiment described above contain the same reference symbols, and different points are mainly described.

Fig. 41 is a top view showing a protrusion of Modification 1 according to the third embodiment. As figure 41 shows, the two front faces 17C have different sizes.

According to Tire 1 of Modification 1 on

accordance with the third mode, it is possible to allow

!

the fact that a centrifugal force causes fluid to flow obliquely outward in the radial direction of the tire. In this way, the flow of fluid passing around the protrusion 17 can be smoothly accelerated, and the tire temperature can be efficiently reduced.

Modification 2 according to the third mode

In the above description of the protrusion 17, according to the third embodiment given above, the protrusion 17 has the rear face 17D formed substantially parallel to the protrusion radial direction centerline CL. However, the following modifications can be made. Note that the same parts as those of protrusion 17 according to the third embodiment described above contain the same reference symbols, and different points are mainly described.

Fig. 42 is a perspective view showing a protrusion of Modification 2 according to the third embodiment. Part (a) of Fig. 43 is a top view showing the protrusion of Modification 2 according to the third embodiment (a view which is seen on arrow A of Fig. 42). Part (b) of Fig. 43 is a cross-sectional view showing the protrusion of Modification 2 according to the third embodiment viewed in the radial direction of tire (a cross-sectional view B-B of Fig. 42). Part (c) of Fig. 43 is a front view showing the bulge of Modification 2 according to the third embodiment seen in the direction of tire rotation (a view that is seen on arrow C of Fig. 42).

As Figures 42 and 43 show, the protrusion 17 is formed of the inner face 17A, the outer face 17B, two front faces 17C, two rear faces 17D and the bulge face 17E.

The protrusion 17 is provided with two rear convex portions 17D-1 and a single rear concave portion 17D-2 rearward, in the tire rotation direction, of the radial radial direction centerline CL. The rear convex portions 17D-1 protrude backward in the tire rotation direction, and the rear concave portion 17D-2 is concave in the rearward rotation direction.

As part (a) of Fig. 43 shows, the rear convex portions 17D-1 and the rear concave portion 17D-2 are linearly formed. The two rear faces 17D are the same size. Note that the two rear faces 17D are not limited to being the same size, and may of course be different sizes.

Although described above as such, the protrusion 17 is not limited to having the rear convex portions 17D-1 and the rear concave portion 17D-2 rearwardly in the tire rotation direction of the radial protrusion axis CL. For example, as part (a) of Fig. 44 shows, only the rear convex part 17D-1 may be provided. There is no limitation as long as any one between the rear convex portion 17D-1 and the rear concave portion 17D-2 is provided. In addition, although described above as such, the protrusion 17 is not limited to being provided with two rear convex portions 17D-1 and the single rear concave portion 17D-2 rearward, in the direction of tire rotation, of the steering centerline. radial protrusion CL. For example, as part (b) of Fig. 44 shows, the rear face 17D may be formed of three rear convex portions 17D-1 and two rear concave portions 17D-2.

Additionally, although described above as such, the rear convex portions 17D-1 and the rear concave portion 17D-2 are not limited to being linearly formed. For example, the following modifications may of course be made. Specifically, as part (c) of Fig. 44 shows, only the rear convex part 17D-1 can be formed into a curve. As part (d) of Fig. 44 shows, three rear convex portions 17D-1 individually having a curved end and two rear concave portions 17D-1 individually having a curved end may be formed. In addition, as part (e) of Fig. 44 shows, a rear concave portion 17D-2 may be formed in a curve between two rear convex portions 17D-1.

According to tire 1 of Modification 2 in accordance with the third embodiment, the rear convex portion 17D-1 is provided rearward, in the tire rotational direction, of the radial radial direction centerline CL. Therefore, backward flowing fluid can be smoothly returned to the main flow. In this way the tire temperature can be reduced efficiently.

In addition, the provision of the rear concave portion 17D-2 to the rear, in the tire rotational direction, of the radius of the radius of direction CL makes the bulge 17 volume smaller and the distance between the basal portion of the bulge 17 and the 15 shorter tire surface. Thus, an increase in temperature at the basal part of the protuberance 17 can be suppressed.

In addition, by providing the rear convex portion 17D-1 and the rear concave portion 17D-2 rearward, in the tire rotation direction, of the radial radial direction centerline CL, not only can the flow of fluid passing around of the protuberance 17 being accelerated, an increase in temperature at the basal part of the protuberance 17 may be suppressed. Consequently, the tire temperature can be reduced more efficiently.

Modification 3 according to the third mode

In the above description of the protuberances 17 according to the third embodiment, the protuberance 17 is formed on a parallelogram when viewed in the radial tire direction (a cross-sectional view B-B). However, the following modifications can be made. Note that the same parts as those of protrusion 17 according to the third embodiment described above contain the same reference symbols, and different points are mainly described.

Fig. 45 is a perspective view showing a protrusion of Modification 3 according to the third embodiment. Part (a) of Fig. 46 is a top view showing the protrusion of Modification 3 according to the third embodiment (a view that is seen on arrow A of Fig. 45). Part (b) of Fig. 46 is a side view showing the bulge of Modification 3 according to the third embodiment viewed in the radial direction of tire (a view that is seen on arrow B of Fig. 45). Part (c) of Fig. 46 is a front view showing the bulge of Modification 3 according to the third embodiment seen in the direction of tire rotation (a view that is seen on arrow C of Fig. 45).

As Figures 45 and 46 show, the protrusion 17 is formed of the inner face 17A, the outer face 17B, and the protrusion face 17E. The bulging face 17E bends. Accordingly, the protrusion 17 is formed into a semi sphere when viewed in the radial direction of the tire.

As part (b) of Fig. 46 shows, the front projection angle (Θ5) and the rear projection angle (Θ6) are individually set to a value.

between 45 ° and 135 ° inclusive. It is especially preferable

f

Set the front bulge angle (Θ5) and rear bulge angle (Θ6) to a value between 70 ° and 110 ° inclusive to effectively reduce tire temperature.

Although described above as such, the bulge 17 is not limited to being formed in a semi sphere when viewed in the radial tire direction. For example, the following modifications can be made. Specifically, as Figure 47 shows, the protrusion 17 may be formed into a triangle when viewed in the radial tire direction. As Figure 48 shows, the protrusion 17 may be formed into a trapezoid when viewed in the radial direction of the tire. Here, the trapezoid has a lower face (the underside of the boss 17, which is in contact with the tire surface 15) wider than the boss face 17E. In addition, as Fig. 49 shows, the protrusion 17 may be formed into a trapezoid when viewed in the radial tire direction. Here the trapezoid has a narrower underside than the bulge face 17E.

According to tire 1 of Modification 2 according to the third embodiment, the flow of fluid passing around the protrusion 17 may be gently accelerated. In this way the tire temperature can be reduced efficiently.

In addition, by setting the front bulge angle (Θ5) and the rear bulge angle (Θ6) to a value between 45 ° and 135 ° inclusive, the fluid flow having collided with front side 19A (the front side of the bulge face 17E) may increase a pressure near the front 19A. In this way, the flow of fluid passing around the protrusion 17 may be further accelerated.

Modification 4 according to the third mode

In the above description of bulge 17 according to

with the third embodiment, the protuberance 17 is formed in

1

a parallelogram when viewed in the direction of tire rotation (in a view of arrow C). However, the following modifications can be made. Note that the same parts as those of protrusion 17 according to the third embodiment described above contain the same reference symbols, and different points are mainly described.

Fig. 50 is a perspective view showing a protrusion of Modification 4 according to the third embodiment. Part (a) of Fig. 51 is a top view showing the protrusion of Modification 4 according to the third embodiment (a view which is seen on arrow A of Fig. 50). Part (b) of Fig. 51 is a cross-sectional view showing the protrusion of Modification 4 according to the third embodiment viewed in the radial direction of tire (a cross-sectional view B-B of Fig. 50). Part (c) of Fig. 51 is a front view showing the protrusion of Modification 4 according to the third embodiment seen in the direction of tire rotation (a view that is seen on arrow C of Fig. 50).

As figures 50 and 51 show, the protrusion 17 is formed of two front faces 17C, the rear face 17D, and two protrusion faces 17E. The protruding faces 17E curve. Accordingly, the protrusion 17 is formed into a semi sphere when viewed in the direction of tire rotation.

As part (c) of Fig. 51 shows, the maximum internal angle (Θ7) and maximum external angle (Θ8) are individually set to a value between 45 ° and 135 ° inclusive. It is especially preferable to set the inner maximum angle (Θ7) and the outer maximum angle (Θ8) to a value between 70 ° and 110 ° inclusive to effectively reduce the tire temperature.

Although described above as such, the bulge 17 is not limited to being formed in a semi sphere when viewed in the direction of rotation of the tire. For example, the following modifications can be made. Specifically, as Fig. 52 shows, the protrusion 17 may be formed into a triangle when viewed in the direction of tire rotation. As Fig. 53 shows, the protrusion 17 may be formed into a trapezoid when viewed in the direction of tire rotation. Here, the trapezoid has a broader underside than the bulge face 17E. In addition, as Fig. 54 shows, the protrusion 17 may be formed into a trapezoid when viewed in the direction of tire rotation. Here the trapezoid has a narrower underside than the bulge face 17E.

According to tire 1 of Modification 4 according to the third embodiment, the flow of fluid passing around the protrusion 17 may be gently accelerated. In this way the tire temperature can be reduced efficiently. Additionally, the maximum internal angle (Θ7) and the maximum external angle (Θ8) are set to a value between 45 ° and 135 ° inclusive. Thus, when fluid spreads around the protuberance 17 by colliding with the front faces 17C, the flow of fluid thereby separating from (spreading around) the protuberance 17 can certainly be accelerated.

EXAMPLES ACCORDING TO THIRD MODE

Next, to further clarify the effects of the present invention, the results obtained from tests performed using the following tires according to comparative examples 1 to 3 and examples 1 to 23 will be described. It should be noted that these examples in no way limit the present invention.

Data on each tire was acquired by measurement under the following conditions.

Tire Size: 28 5 / 50R20

Wheel size: 8JJx20

Internal pressure condition: OkPa (in one station)

bored)

Charging Condition: 9.8kN

As shown in the following tables 7 through 9, test tires A, test tires B, and test tires C have been prepared to test the durability of each tire. The tires according to comparative examples 1 to 3 have no bulges. The tires according to examples 1 to 23 have bulges, and have different bulge configurations (such as shapes, radial bulge steering length (L), and maximum bulge height (H)), as shown in following tables 10 to 12. TABLE 7 Test Tire A Example Example Example Example Example Example Example Example Example Comparative Example 1 2 3 4 5 6 7 8 9 1 Top View (top) W view Radial tire direction (side) W view iSHt IW tire rotation direction (front) 0/4 length 2 8 2 2 2 2 2 2 radial direction of protrusion (L) Maximum height 2 2 2 0,4 8 2 2 2 2 of protrusion (H) θΐ, Θ2 90 90 90 90 90 50 130 90 90 (degrees) 63 / Θ4 · --- 90 90 90 90 90 90 90 50 50 130 (degrees) Durability 100 101 140 104 104 105 102 105 104 105 69/95 TABLE 8 Test Tire B Example Example Example Example Example Example Example Example Example Comparative Example 10 11 12 13 14 15 16 17 18 2 Top View *> <1 Bulge (top) View of o * rio * * ιΓ \ & radial direction length (side) View of tSTV irr tire rotation direction (front) Length of 0.4 2 8 2 2 2 2 2 2 Radial direction of protection (L) Maximum height 2 2 2 0.4 8 2 2 2 2 of protection (H) )1.02 _ 90 90 90 90 90 50 130 90 90 (degrees) 03.04 90 90 90 90 90 90 90 50 50 (degrees) Durability 100 101 142 104 104 105 103 103 104 104 105 TABLE 9 Test Tire C Example Example 19 Example 20 Example 21 Example 22 Comparative Example 23 Top view the bulge <3> (top) 0 / U “Radial Tire Direction (Side) View Tire Rotation Direction (Front) View Length 0.4 2 8 2 2 Radial guard of direction (L) Maximum height 2 2 2 0.4 8 of guard (H) Durability 100 101 130 104 104 105 Durability

Each of the tires was fitted into a drum tester placed inside, rotated at a constant speed (90 km / h), and measured for its durable distance to breakage. The tire durability of each of comparative examples 1 to 3 was set to '100'. So the durability of each of the other tires was rated at a relative value of 100. Note that the higher the index, the better the durability.

As a result, as shown in tables 7 to 9, it has been found that tires according to examples 1 to 23 have excellent durability compared to tires according to comparative examples 1 to 23.

3. Particularly, similar to the examples, according to the second embodiment, it was found that the tire satisfying the ratio 1.0 <L / H <50.0 has excellent durability, as shown in figure 36. Also, it was found that the tire having the maximum protrusion height (H) of 0.3mm to 15mm has excellent durability as shown in figure 37.

Fourth modality

In the following, the configuration of a protrusion 17 according to a fourth embodiment will be described with reference to figures 55 and 56. Note that the same parts as those of tire 1 according to the first embodiment described above contain the same reference symbols, and different parts will be described primarily. Namely, points such as tire configuration I and arrangement and arrangement density of protuberances 17 are not described repeatedly. However, some points may be partially repeated.

Fig. 55 is a perspective view showing the protrusion according to the fourth embodiment. Part (a) of Fig. 56 is a top view showing the protuberance according to the fourth embodiment (a view which is seen on arrow A of Fig. 55). Part (b) of Fig. 56 is a cross-sectional view showing the protrusion according to the fourth embodiment viewed in the radial tire direction (a cross-sectional view B-B of Fig. 55). Part (c) of Fig. 56 is a front view showing the protrusion according to the fourth embodiment seen in the direction of tire rotation (a view that is seen on arrow C of Fig. 55).

As Figures 55 and 56 show, the protrusion 17 is formed of an inner face 17A, an outer face 17B, a front face 17C, a rear face 17D, and a protrusion face 17E.

As part (a) of Fig. 56 shows, in a top view of the protrusion, the front face 17C has a front inner point (Q1) located in an innermost position in the radial tire direction, and a front outer point (Q2). located in a more outer position in the radial direction of tire. The front inner point (Q1) is located forward in the tire rotation direction of the front outer point (Q2). In other words, a bulge front line FL that connects the front inner point (Q1) and the front outer point (Q2) inclines with respect to the radial direction centerline of bulge CL.

In a top view of the protrusion 17, each between inner face 17A, outer face 17B, front face 17C, and rear face 17D is linearly (flattened) formed.

As part (b) of Fig. 56 shows, the boss 17 is formed in a parallelogram in a radial tire direction view, which is a view in which the boss 17 is viewed in the radial tire direction. Furthermore, as part (c) of Fig. 56 shows, the protuberance 17 is formed on a parallelogram also in a view in the direction of tire rotation, which is a view in which the protuberance 17 is viewed from the front side of the tire. Tire rotation direction.

Accordingly, the inner face 17A and the outer face 17B are formed substantially perpendicular to the protruding radial direction centerline CL. In addition, the front face 17C (FL protrusion front line) tilts relative to the CL protrusion radial direction centerline. The rear face 17D is formed substantially parallel to the protruding radial direction centerline CL. Bulge face 17E is formed

'I

substantially parallel to the tire surface 15.

As part (b) of Fig. 56 shows, a front angle (Θ1) and a rear angle (02) are individually set to a value between 45 ° and 135 ° inclusive. It is especially preferable to set the front angle (Θ1) and rear angle (Θ2) to a value between 70 ° and 110 ° inclusive to reduce tire temperature efficiently.

As part (c) of Fig. 56 shows, an inner angle (Θ3) and an outer angle (04) are individually set to a value between 45 ° and 135 ° inclusive. It is especially preferable to set the inner angle (Θ3) and the outer angle (04) to a value between 70 ° and 110 ° inclusive.

Operations and effects according to the fourth

modality

According to tire 1 in accordance with the fourth embodiment described above, the front inner point (Q1) is located forward, in the direction of tire rotation, of the front outer point (Q2) (the front face 17C (front line of protrusion FL) tilts relative to the radial direction centerline of protuberance CL). This allows a pressure to increase on the front side (front face 17C) in the direction of tire rotation of the protrusion 17. This pressure increase can accelerate the flow of fluid passing around the protrusion 17 (i.e., it can improve a heat dissipation rate of tire temperature). This way, without a new breakdown, tire 1 can efficiently reduce tire temperature while maintaining overall driving performance.

Specifically, as Figure 57 shows, as tire 1 rotates, the protrusion 17 causes fluid (termed a main flow Sl below) in contact with tire surface 15 (the side portion SW) to separate from the portion of SW side. Then the main flow SL flows over an edge E of the nub 17 and accelerates towards the rear side in the direction of tire rotation (namely rearward).

Then, by tilting the front face 17C (front protrusion line FL) relative to the radial direction centerline of protrusion CL, the main flow Sl is separated from the front inner point (Q1) located forward in the direction of tire rotation. , from the front external point (Q2) before flowing over edge E. Thus, the main flow Sl is accelerated when flowing over edge E.

The thus accelerated main flow SL flows in a direction perpendicular to the tire surface 15 on the rear side of the rear face 17D. At that time, fluid S3 flows a part (region) where fluid flow remains, thereby drawing heat remaining on the rear side of rear face 17D, and then merging again with main flow SI.

Main stream S1 flows over edge E and thereby accelerates, and fluid S3 draws heat and then again fuses with main stream S1. This allows for a temperature reduction over a large area of the tire. In particular, a temperature may be reduced at a basal portion T1 of the protuberance 17 and in a region T2 where the main flow SL contacts in the perpendicular direction.

Modification 1 according to the fourth mode

In the above description of the protrusion 17, according to the fourth embodiment, the inner face 17A and the outer face 17B forming the protrusion 17 are formed substantially perpendicular to the radial direction centerline of protrusion CL. However, the following modifications can be made. Note that the same parts as those of protrusion 17 according to the fourth embodiment described above contain the same reference symbols, and different points are mainly described.

Fig. 58 is a top view showing a Modification protrusion 1 according to the fourth embodiment. As parts (a) and (b) of Fig. 58 show, the inner face 17A and the outer face 17B incline relative to the radial protrusion centerline CL. Also in this case, the front inner point (Ql) is located forward, in the direction of tire rotation, of the front outer point (Q2). In other words, the front face 17C (front protrusion line FL) tilts relative to the radial direction centerline of protrusion CL.

According to tire 1 of Modification 1 according to the fourth embodiment, the flow of fluid passing around the protrusion 17 may be gently accelerated. In this way the tire temperature can be reduced efficiently.

Modification 2 according to the fourth mode

In the above description of protrusion 17, according to the fourth embodiment, the rear face 17D is formed substantially parallel to the protrusion radial direction centerline CL. However, the following modifications can be made. Note that the same parts as those of protrusion 17 according to the fourth embodiment described above contain the same reference symbols, and different points are mainly described.

Fig. 59 is a perspective view showing a protrusion of Modification 2 according to the fourth embodiment. Part (a) of Fig. 60 is a top view showing the protrusion of Modification 2 according to the fourth embodiment (a view which is seen on arrow A of Fig. 59). Part (b) of Fig. 60 is a cross-sectional view showing the protrusion of Modification 2 according to the fourth embodiment viewed in the radial direction of tire (a cross-sectional view B-B of 59). Part (c) of Fig. 60 is a front view showing the protrusion of Modification 2 according to the fourth embodiment seen in the direction of tire rotation (a view which is seen on arrow C of Fig. 59).

As Figures 59 and 60 show, the protrusion 17 is formed of the inner face 17A, the outer face 17B, the front face 17C, two rear faces 17D, and the bulge face 17E.

The protrusion 17 is provided with two rear convex portions 17D-1 and a single rear concave portion 17D-2 rearward, in the tire rotation direction, of the radial radial direction centerline CL. The rear convex portions 17D-1 protrude backward in the tire rotation direction, and the rear concave portion 17D-2 is concave in the tire rotation direction.

The rear convex portions 17D-1 and the rear concave portion 17D-2 are linearly formed. The two rear faces 17D are the same size. However, the two rear faces 17D are not limited to being the same size and may, of course, be different sizes.

Although described above as such, the protrusion 17 is not limited to being provided at its rear with the convex rear portions 17D-1 and the rear concave portion 17D-2 rearward in the direction of tire rotation of the centerline. of radial direction of bulge CL. For example, as part (a) of Fig. 61 shows, only the rear convex part 17D-1 may be provided. There is no limitation as long as either between the rear convex portion 17D-1 and the rear concave portion 17D-2 is provided.

In addition, although described above as such, the protrusion 17 is not limited to having two rear convex portions 17D-1 and single rear concave portion 17D-2 rearward, in the tire rotation direction, of the radial centerline of bulge CL. For example, as part (b) of Fig. 61 shows, three rear convex portions 17D-1 and two rear concave portions 17D-2 may be provided.

Furthermore, although described above as such, the protrusion 17 is not limited to being linearly formed. For example, the following modifications can be made. Specifically, as part (c) of Fig. 61 shows, only the rear convex part 17D-1 can be formed into a curve. As part (d) of Fig. 61 shows, three rear convex portions 17D-1 each having a curved end and two rear concave portions 17D-1 each having a curved end may be formed into a curve. In addition, as part (e) of Fig. 61 shows, the rear concave part 17D-2 may be formed into

a curve between two rear convex parts 17D-1.

In accordance with tire 1 of Modification 2, in accordance with the fourth embodiment, the rear convex portion 17D-1 is provided rearward, in the tire rotational direction, of the radial direction centerline of

bulge CL. Therefore, the backward flowing fluid can be gently returned to the main flow. In this way the tire temperature can be reduced efficiently.

In addition, the provision of the rear concave part

17D-2 to the rearward, in the direction of tire rotation, of the radial radial direction centerline CL makes the bulge volume 17 smaller and the distance between the basal portion of the bulge 17 and the shorter tire surface 15. Thus, an increase in temperature in the

protuberance 17 may be suppressed.

In addition, by providing the rear convex part 17D-1 and rear concave part 17D-2 backward, in the tire rotation direction, of the radial radial direction centerline CL, not only can the flow of

As fluid passing around the protuberance 17 is accelerated, an increase in temperature at the basal portion of the protuberance 17 may be suppressed. Consequently, the tire temperature can be reduced more efficiently. Modification 3 according to the fourth mode

In the above description of the protuberance 17, according to the fourth embodiment, the protuberance 17 is formed in a parallelogram when viewed in the radial tire direction (a cross-sectional view B-B). However, the following modifications can be made. Note that the same parts as those of protrusion 17 according to the fourth embodiment described above contain the same reference symbols, and different points are mainly described.

Fig. 62 is a perspective view showing a protrusion of Modification 3 according to the fourth embodiment. Part (a) of Fig. 63 is a top view showing the protrusion of Modification 3 according to the fourth embodiment (a view which is seen on arrow A of Fig. 62). Part (b) of Fig. 63 is a side view showing the protrusion of Modification 3 according to the fourth embodiment seen in the radial direction of tire (a view which is seen in arrow B of Fig. 62). Part (c) of Fig. 63 is a front view showing the protrusion of Modification 3 according to the fourth embodiment seen in the direction of tire rotation (a view that is seen on arrow C of Fig. 62).

As Figures 62 and 63 show, the protrusion 17 is formed of the inner face 17A, the outer face 17B, and the protrusion face 17E. The bulging face 17E bends. Accordingly, the protrusion 17 is formed into a semi sphere when viewed in the radial direction of the tire.

As part (a) of Fig. 63 shows, in a top view of the protrusion, a front portion 35 (front face) has the front inner point (Q1) located in an innermost position in the radial direction of the tire and the front outer point. (Q2) located in an outermost position in the radial direction of the tire. The front inner point (Q1) is located forward in the tire rotation direction of the front outer point (Q2). In other words, the front protrusion line FL that connects the front inner point (Q1) and the front outer point (Q2) inclines with respect to the radial direction centerline of protuberance CL.

As part (b) of Fig. 63 shows, the front projection angle (Θ5) and the rear projection angle (06) are individually set to a value between 45 ° and 135 ° inclusive. It is especially preferable to set the front bulge angle (Θ5) and rear bulge angle (Θ6) to a value between 70 ° and 110 ° inclusive to effectively reduce the tire temperature.

Although described above as such, the bulge 17 is not limited to being formed in a semi sphere when viewed in the radial tire direction. For example, the following modifications can be made. Specifically, as Figure 64 shows, the protrusion 17 may be formed into a triangle when viewed in the radial tire direction. As Figure 65 shows, the protrusion 17 may be formed into a trapezoid when viewed in the radial tire direction. Here, the trapezoid has a lower face (the underside of the protrusion 17 which is in contact with the tire surface 15) wider than the protrusion face 17E. In addition, as Fig. 66 shows, the protrusion 17 may be formed into a trapezoid when viewed in the radial tire direction. Here the trapezoid has a narrower underside than the bulge face 17E.

According to tire 1 of Modification 3 according to the fourth embodiment, the flow of fluid passing around the protrusion 17 may be gently accelerated. In this way the tire temperature can be reduced efficiently.

In addition, by setting the front bulge angle (Θ5) and the rear bulge angle (Θ6) to a value between 45 ° and 135 ° inclusive, the fluid flow having collided with front side 19A (the front side of the bulge face 17E) may increase a pressure near the front 19A. In this way, the flow of fluid passing around the protrusion 17 may be further accelerated.

Modification 4 according to the fourth mode

In the above description of bulge 17, according to the fourth embodiment, bulge 17 is formed on a parallelogram when viewed in the direction of tire rotation (in a view of arrow C). However, the following modifications can be made. Note that the same parts as those of protrusion 17 according to the fourth embodiment described above contain the same reference symbols, and different points are described primarily.

Fig. 67 is a perspective view showing a protrusion of Modification 4 according to the fourth embodiment. Part (a) of Fig. 68 is a top view showing the protrusion of Modification 4 according to the fourth embodiment (a view which is seen on arrow A of Fig. 67). Part (b) of Fig. 68 is a cross-sectional view showing the protrusion of Modification 4 according to the fourth embodiment viewed in the radial tire direction (a cross-sectional view B-B of Fig. 67). Part (c) of Fig. 68 is a front view showing the protrusion of Modification 4 according to the fourth embodiment seen in the direction of tire rotation (a view that is seen in arrow C of Fig. 67).

As Figures 67 and 68 show, the protrusion 17 is formed of the front face 17C, rear face 17D, and the protrusion face 17E. The bulging face 17E bends. Consequently, the protrusion 17 is formed into a semi sphere when viewed in the direction of tire rotation.

As part (a) of Fig. 68 shows, in a top view of the protrusion, the front inner point (Q1) is located forward, in the direction of tire rotation, of the front outer point (Q2). In other words, the front protrusion line FL that connects the front inner point (Q1) and the front outer point (Q2) inclines with respect to the radial direction centerline of protuberance CL.

As part (c) of Fig. 68 shows, the inner bulge angle (Θ7) and the maximum outer angle (Θ8) are individually set to a value between 45 ° and 135 ° inclusive. It is especially preferable to set the inner bulge angle (Θ7) and the maximum outer angle (Θ8) to a value between 70 ° and 110 ° inclusive to effectively reduce tire temperature.

Although described above as such, the bulge 17 is not limited to being formed in a half sphere when viewed in the direction of tire rotation. For example, the following modifications can be made. Specifically, as Figure 69 shows, the protrusion 17 may be formed into a triangle when viewed in the direction of tire rotation. As Figure 70 shows, the protrusion 17 may be formed into a trapezoid when viewed in the direction of tire rotation. Here, the trapezoid has a broader underside than the bulge face 17E. Furthermore, as Fig. 71 shows, the protrusion 17 may be formed into a trapezoid when viewed in the direction of tire rotation. Here the trapezoid has a narrower underside than the bulge face 17E.

According to tire 1 of Modification 4 in accordance with the fourth embodiment, the flow of fluid passing around the protrusion 17 may be gently accelerated. In this way the tire temperature can be reduced efficiently.

In addition, by setting the inner bulge angle (Θ7) and the maximum outer angle (08) to a value between 45 ° and 135 °, even when fluid spreads around the bulge 17 by colliding with the front face 17C, the The flow of fluid thereby separating from (spreading around) the bulge 17 can certainly be accelerated.

EXAMPLES ACCORDING TO FOURTH MODE

In the following, to further clarify the effects of the present invention, the results obtained from tests performed using the following tires according to comparative examples 1 to 3 and examples 1 to 23 will be described. It should be noted that these examples in no way limit the present invention.

Data on each tire was acquired by measurement under the following conditions.

Tire Size: 285 / 50R20

Wheel size: 8JJx20

Internal pressure condition: OkPa (in one state

bored)

Loading condition: 9.8 kN

As shown in Tables 10 to 12 below, test tires A, test tires B, and test tires C have been prepared to test the durability of each tire. The tires according to comparative examples 1 to 3 have no protrusions. The tires according to examples 1 to 23 have bulges, and have different bulge configurations (such as shapes, radial bulge steering length (L), and maximum bulge height (H)), as shown in the following Tables 13 to 15. TABLE 10 Test Tire A Example Example Example Example Example Example Example Example Example Comparative Example 1 2 3 4 5 6 7 8 9 1 Top View (top) • s & W view Radial tire direction (side) * srr W IW tire rotation direction (front) view Length 0.4 2 8 2 2 2 2 2 2 radial direction Protectance (L) Maximum Height 2 2 2 0.4 8 2 2 2 2 Protectance (H) Θ1, Θ2 --- 90 90 90 90 90 50 130 90 90 (degrees) Θ3, Θ4 90 90 90 90 90 90 90 50 130 (degrees) Durability 100 101 135 104 104 105 102 10 5 104 105 TABLE 11 Test tire B Example Example Example Example Example Example Example Example Example Comparative example 10 11 12 13 14 15 16 17 18 2 Top view *> ZD ~ from protrusion (top) View of W «Λ? * Radial direction Tire Tread (side) View from W W IW Tire Rotation Direction (Front) Length 0.4 2 8 2 2 2 2 2 2 Protective Radial Steering (L) Maximum Height 2 2 2 0.4 8 2 2 2 2 of protuberance (H) Θ1, Θ2 * “90 90 90 90 90 50 130 90 90 (degrees) Θ3, Θ4 90 90 90 90 90 90 90 50 130 (degrees) Durability 100 101 136 108 104 107 103 105 105 105 105 87/95 TABLE 12 Test Tire C Example Example 19 Example 20 Example 21 Example 22 Comparative Example 3 Top view * => / TI * - from bulge (top) Tire radial direction view (side) Tire rotation direction view (front) 0.4 2 8 2 2 Radial protrusion direction (L) Maximum height 2 2 2 0.4 8 protrusion (H) Durability 100 101 129 104/104 106 Durability

Each of the tires was fitted to an inboard drum testing machine, rotated at a constant speed (90 km / h), and measured for its durable distance to breakage. The tire durability of each of comparative examples 1 to 3 was set to '100'. So the durability of each of the other tires was rated at a relative value of 100. Note that the higher the index, the better the durability.

As a result, as shown in tables 10 to 12, it has been found that tires according to examples 1 to 23 have excellent durability compared to tires according to comparative examples 1 to 3. Particularly, similar to the examples of According to the second embodiment, it was found that the tire that meets the 1.0 <L / H <50.0 ratio has excellent durability, as shown in Figure 36. Also, it was found that the tire having the maximum protrusion height (H) from 0.3 mm to 15 mm has excellent durability as shown in figure 37.

Fifth modality

In the following, the configuration of a tire according to a fifth embodiment will be described with reference to Figure 72. Figure 72 is a cross-sectional view of the tire according to the fifth embodiment taken in the tread direction . Note that the same parts (same configurations) as those of tire 1 according to the first embodiment described above contain the same reference symbols, and different points are mainly described.

As Fig. 72 shows, a tire 100 is a truck and bus radial tire (TBR) in which ribs 130A are formed on a tread portion 13. Tire 100 has more layers on a belt layer 11 and has a tire radius greater than the passenger car radial tire (PCR) described in the first embodiment.

In tire 100, when heat on the surface of a bead portion 3 is to be dissipated, protrusions 17 may be disposed inwardly in the radial tire direction of the maximum tire width position (i.e. on the side of the bead portion 3 ). When the belt layer 11 has many layers, the protrusions 17 may be disposed outwardly in the radial tire direction from the maximum tire width position (i.e. on the part side of the tread 13).

Tire 100 is not limited to the passenger car radial tire (PCR) described in the first embodiment or the truck and bus radial tire (TBR) described in this embodiment. For example, tire 100 may be a heavy load tire as follows. Specifically, as Fig. 73 shows, tire 100 may be a radial tire for a construction vehicle (such as a crader or shovel loader) wherein only shoulders 130B are formed in the tread portion 13. In addition, as the 74 shows the tire 100 may be a radial tire for a construction vehicle (such as a dump truck or a crane) in which the ribs 130A and the shoulders 130B are formed on the tread portion 13. In addition, the tire 100 need not necessarily be a radial tire, and may of course be an oblique tire.

Operations and effects according to the fifth

modality

According to tire 100 in accordance with the fifth embodiment described above, even when a tire other than a passenger car radial tire (PCR) is used, the tire can efficiently reduce the tire temperature while maintaining overall tire performance. direction.

Sixth modality

In the following, the configuration of a tire according to a sixth embodiment will be described with reference to figure 75. Part (a) of figure 75 is a partially enlarged perspective view showing a tread portion of the tire according to with the sixth mode. Part (b) of Fig. 75 is a cross-sectional view showing the proximity of a notch in the tire according to the sixth embodiment. Note that the same parts as those of tire 1 according to the first embodiment described above contain the same reference symbols, and different points are mainly described.

As parts (a) and (b) of figure 75 show, multiple protrusions 17 are provided in a notch 13A formed in a tread portion 13. Protrusions 17 protrude from a tire surface 15 (within notch 13A ) and generate turbulence. Note that the notch 13A includes a rib 130A and a shoulder 130B described in the fifth embodiment.

Each of the protrusions 17 is provided continuously from a lower face 13b to a side face 13c of notch 13A. Note that the protrusion 17 does not necessarily have to be supplied continuously from the bottom face 13b to the side face 13c of the notch 13A, and can be divided into a predetermined range as shown in Fig. 76.

In addition, the protrusion 17 need not necessarily be provided on the underside 13b and side face 13c of the notch 13A. For example, as Fig. 77 shows, the protrusion 17 may be provided continuously at least on one of the side faces 13b of the notch 13A, or as Fig. 78 shows, it may be divided into a predetermined range at least one of the side faces 13b. of notch 13A.

Alternatively, as part (a) of Fig. 79 shows, the protrusion 17 may be continuously provided only on the underside 13c of notch 13A, or as part (b) of Fig. 79 shows, it may be divided to a predetermined interval only on the face. bottom 13c of notch 13A. Moreover, as Fig. 80 shows, such a protrusion 17 is of course also applicable when the protrusion 17 is provided only on a shoulder notch 13B.

Operations and effects according to the sixth

modality

According to tire 1 according to the sixth embodiment described above, the protrusion 17 is provided in the notch 13A formed in the tread portion 13, at least one of the underside 13a and side faces 13b. Thereby, the temperature of the tire may be reduced in the vicinity of the notches 13A formed in the tread portion 13 which is closest to the extreme part of the belt layer 11 where separation and cracking are likely to occur. Therefore durability can be improved as well.

Seventh modality

In the following, the configuration of a tire according to a seventh embodiment will be described with reference to Fig. 81. Fig. 81 is a cross-sectional view of the tire according to the seventh embodiment, taken in the tread direction. Note that the same parts as those of tire 1 according to the first embodiment described above contain the same reference symbols, and different points are mainly described.

As figure 81 shows, multiple protuberances 17 are provided inwardly in the tread direction of an inner lining 9. The protuberances 17 protrude from an inner face of the tire (the inner lining 9) and generate turbulence.

When heat on the surface of a tread portion 3 is to be dissipated, the protrusions 17 may be disposed inwardly in the radial tire direction of the maximum tire width position (i.e. on the bead portion 3 side) . When a belt layer 11 has many layers, the protrusions 17 may be disposed inwardly in the radial tire direction of the maximum tire width position (i.e. on the rear side of a tread portion 13, or the like). ).

Operations and effects according to the fifth

modality

In tire 1 according to the seventh embodiment described above, the protuberances 17 are provided on the inner face of the tire. Accordingly, the temperature of the inner surface of the tire, particularly the inner surface of the tire in a punctured state, may be reduced. Durability can therefore be improved as well.

Specifically, when tire 1 becomes a punctured state, fluid inside the tire (internal gas) and fluid outside the tire (external gas) exchange heat through a hole made in tire I. At this time, by providing the protuberances 17 on the face Inside the tire, the fluid inside the tire can be accelerated to allow smooth heat exchange. Consequently, the temperature of the tire inner face in a punctured state may be reduced.

Particularly when a tire with a side reinforcement layer 7 (flat tire) becomes a punctured state, the temperature within the tire rises compared to a tire without a side reinforcement layer 7. therefore, the provision of protrusions 17 on the inner surface of the tire allows for a temperature reduction within the tire and thereby allows for improved durability.

Other modalities

The content of the present invention has been disclosed as above using the embodiments of the present invention. However, it should not be understood that the present invention is limited by the description and drawings that form part of this disclosure.

Specifically, although described as such, the tire 1 is not limited to having the side reinforcement layer 7 (namely, being an empty rotating tire), and may not have a side reinforcement layer 7.

In addition, the protrusion 17 may be formed as a combination of the various shapes described in the first to seventh embodiments, and may of course include a shape not shown in the drawings.

In addition, when opposing faces (e.g. inner face 17A and outer face 17B, front face 17C and rear face 17D, or bulge face 17E and bottom face (tire surface 15)) are flat, opposite faces do not necessarily have to be formed parallel to each other. For example, either of the opposing faces may slope (or rise or fall) from the front face 17C to the rear face 17D, or may of course be asymmetric. This disclosure will make various alternative embodiments, examples, and operating techniques apparent to those skilled in the art. Therefore, the technical scope of the present invention should be defined only by the specific subject matter of the invention according to the scope of the invention as defined by the appended claims reasonably understood from the above description.

Industrial Applicability

As described above, the tire of the present invention allows the tire temperature to be efficiently reduced while maintaining overall driving performance. Accordingly, the present invention is useful as, for example, a technique for manufacturing tires.

Claims (12)

1. A tire comprising turbulence bumps on the surface of a tire, each of the turbulence bumps having an acute edge portion, where the following relationships are met: <formula> formula see original document page 97 </formula> " R "is a tire radius being a distance from a rim center to an outermost position in a radial tread direction," H "is a maximum protrusion height being a distance from the tire surface to a position at which each turbulent bulge protrudes farther from the tire surface, "p" is a circumferential bulge direction interval being a gap between adjacent turbulent bulges in a tire rotate direction, "e" is a steering range radial protuberance being a gap between the bulges that generate adjacent turbulence in one direction orthogonal rotation direction substantially orthogonal to the tire rotation direction, "L" is a radial bulge steering length being a maximum length of each turbulence generating bulge in the orthogonal rotation direction, and "w" is a steering length circumferential bump being a maximum length of each turbulence generating bump in the direction of tire rotation. Pneumatic according to claim 1, wherein an average arrangement density (p) of the turbulence generating bulges is 0.0008 to 13 pieces / cm2. Pneumatic according to claim 2, wherein the average arrangement density (p) of the turbulence-producing bulges gradually decreases from an inner side in a radial tire direction to an outer side in a radial tire direction. Pneumatic according to claim 1, wherein the turbulence-producing bulges are arranged at predetermined intervals in respective directions: a direction in which the turbulence is generated to flow in a direction opposite to the tire rotation direction; and an orthogonal direction to turbulence, and are arranged in a dispersed mode in which the adjacent turbulent generating protuberances in the turbulence generating direction are arranged at respective positions offset from each other. Pneumatic according to claim 4, wherein a circumferential protrusion (CL ') centerline tilts with respect to the tire rotation direction by 10 ° to 20 ° with a rear side thereof in the direction of tire rotation being outwardly in the radial direction of the tire from a front side thereof in the tire rotation direction and the circumferential bulge direction line (CL ') being a line connecting the centers of the respective bulges that generate adjacent turbulence in the tire rotation direction. Pneumatic according to claim 1, wherein in a bulge top view being a view in which the turbulent bulge is viewed from the top, a front face of the turbulent bulge at least partially curves the face. located forward, in the direction of tire rotation, of a protruding radial direction (CL) axis, and a front angle (01) and rear angle (02) are individually set to a value between 45 ° and 135 ° inclusive, the front angle (01) being an angle formed between the tire surface and the front face, the rear angle (02) being an angle formed between the tire surface and a rear face located in the rearward direction. radial direction centerline (CL) of tire rotation. Pneumatic according to claim 1, wherein in a bulge top view being a view in which each turbulent bulge is viewed from the top, a front convex portion is provided forward in the direction of tire rotation; the radial direction centerline (CL) of the bulge, the front convex part protruding forward in the direction of tire rotation. Pneumatic according to claim 1, wherein in a protrusion top view being a view in which each turbulent protrusion is viewed from the top, a front face located forward, in the direction of rotation of the tire, of the line. protruding radial center (CL) center has a front inner point (Ql) located in an innermost position in a radial tire direction, and a front outer point (Q2) located in an outermost position in a radial tire direction, the front inner point (Q1) being located forward, in the direction of tire rotation, of the front outer point (Q2). Pneumatic according to claim 1, wherein in a protrusion top view being a view in which each turbulent protrusion is viewed from the top, at least one of a rear convex portion and a rear concave portion is provided for rearward, in the direction of tire rotation, of the radial bulge centerline (CL), the rear convex portion protruding backward in the direction of tire rotation, the rear concave portion being concave forward in the tire rotation direction . Pneumatic according to claim 1, wherein an inner angle (Θ3) and an outer angle (04) are individually defined at a value between 45 ° and 135 °, inclusive, the inner angle (03) being an angle formed between the tire surface and an inner face located in an innermost position in a radial tire direction, the outer angle (04) being an angle formed between the tire surface and an outer face located in an outermost position in the direction tire radial. Pneumatic according to claim 1, wherein a maximum front angle (05) and a maximum rear angle (06) are individually defined at a value between 45 ° and 135 °, including the maximum front angle (05). being an angle formed between a projecting position and a position where the tire surface intersects with a front face located forward, in the direction of tire rotation, of the protruding radial direction centerline (CL), the most projected position is projecting farthest from the tire surface, the maximum rear angle (06) being an angle formed between the most projected position and a position where the tire surface intersects with a rear face located rearward in the direction of tire rotation of the line radial direction center (CL). Pneumatic according to claim 1, wherein an inner maximum angle (07) and an outer maximum angle (08) are individually defined to a value between 45 ° and 135 °, including the inner maximum angle (07). being an angle formed between a more projected position and a position where the tire surface intersects an inner part located at an innermost position in a radial direction of the tire, the most projected position projecting farthest from the tire surface, the angle outer maximum (08) being an angle formed between the most projected position and a position where the tire surface intersects with an outer part located at an outermost position in the radial direction of the tire.